tv Day 9 of Trial for Derek Chauvin Accused in Death of George Floyd CSPAN April 9, 2021 4:44am-10:23am EDT
do you swear or affirm under p enalty of perjury the testimony you are about to give is the truth and nothing but the truth? >> i do. >> and doctor come if you wouldn't mind removing a mask for your testimony and also to make sure with the microphone is properly placed we will have you state your full name. >> martin towbin. >> good morning, doctor towbin. >> good morning. >> would you tell us what is your employment? >> i'm a physician in pulmonary critical care medicine. >> whereabouts? >> in chicago at -- and medical
school. >> and is hines va hospital a large facility? >> it used to be the largest va hospital in the country i think. that is now been superseded by one or two others. >> and do specialize in pulmonology? >> i specialize in pulmonology and the critical care medicine. >> would you tell the jury what pulmonology is? >> pulmonologist is a study of the lungs. it deals with all diseases that affect the respiratory system,, so the lungs, the chest wall. >> so what are the various element components of the respiratory system other than the lungs and chest wall? >> the respiratory system begins at the nose and the mouth. it goes down to the back of the throat, down to the windpipe out to the bronchial tubes and then down at the bottom down to the
air sacs. these are the small great like structures at the bottom were all the gas exchange takes place, where oxygen gets in and carbon dioxide is removed. >> so this is the system for getting oxygen into the body? >> correct. that is the prime purpose is to get oxygen in. >> now at heinz hospital do you work in intensive care unit? >> yes, i work in the medical intensive care unit. >> and that's considered critical care? >> same as critical care. these words all have the same meeting. >> is critical care different from emergency medicine? >> yes, it's very different than emergency medicine. emergency medicine is kind of the front door of the hospital, that is the triage area where you separate out what people need to go, where is the critical care is will you take a very, very sickest people. >> what kind of patience d.c. in
the icu? >> in the icu, probably more than half our patients were requiring mechanical ventilation, so they're on a respirator to help them with their breathing. and another substantial number will not be on a respirator but their primary problems relates to their lungs. so that might make up 70% or so and then the remaining patients will have drug overdoses, alcohol withdrawal, diabetic, sepsis, things like that. >> do you only see patients in need of respiratory care? >> no. once they come into the icu they are our patients. i am the primary care physician for everybody who comes into the icu. >> and how long have you been a physician? >> i have been a physician for three months short of 46 years, so over 45 years. >> where did you go to school? >> i went to medical school in
dublin, ireland, and i took my degree there. >> not that anybody notice the accident, but are you from dublin? >> no, i'm not from dublin. i'm from a small village in rural ireland. >> what degrees do you hold? >> i'm sorry? >> what degrees? >> that degree i hope is the m.d. degree which is the irish equivalent of the american m.d., and then subsequently i've got an m.d. through research. >> are you currently licensed? >> yes, i am licensed in the state of illinois. in the past i was licensed in ireland and england and the number of u.s. states, but i have let them all lapsed because the only place i am practicing is in illinois. >> are you board-certified? >> yes, i am board-certified in internal medicine, pulmonary medicine and critical care
medicine. >> so you still are activelg for patients? >> yes. i am taking care of patients in the icu last week, and on monday i go straight back into the icu again. >> how long have you held positions at loyola university school of medicine? >> i've been a loyal and heinz for 32 years almost. >> before going to loyola, where you practicing medicine somewhere else pgh yes. i spent seven years at the university of texas at houston. >> did also set up a sleep clinic in houston? >> yes, i did. that would've been in the early '80s concise set up one of the very first sleep labs in the united states for evaluating patients with obstructive sleep apnea. >> so how does sleep disorders fit within your expertise? >> because this is related again to breathing, and the problems
with sleep particularly people who senator, the people who senator during the nighttime they include their upper airway. they can totally stop breathing, 500, six are times times a night ensuring that level of oxygen in the blood will go very low. the basic problem in sleep apnea is because the soft palate, the roof of your mouth is your heart, and then if you look in -- it's the little piece hanging out at the back and that is your soft palate and that jams in against the back of your throat and it gets occluded. five times a night in in somebody who has sleep apnea. >> and does that kind of research or science or medicine relate to your work in this case? >> yes, it is extremely pertinent to the case of mr. floyd because obviously in sleep apnea the problem is at the back of the throat. as we will see in mr. floyd,
essential problem of where the obstruction is occurring is in the hypopharynx which is again at the back of the throat. so it has an awful lot of overlap to patients with sleep apnea. >> will come back to that hypopharynx in a little bit. are you also engaged in medical research? >> i'm sorry? >> are i also engaged in medil research? >> yes. i have been doing medical research since the early '80s, since about 1981. >> what kind of research have you been doing? >> all of my research is related basically to breathing. so what is either looking at breathing in patients with lung disease, people of lung disease who walked in the door to the clinic, and also patients or in the icu, and particularly patients who are requiring the
type of ventilation but i do a lot of research that has nothing to do with clinical medicine, just to know how people breathe. >> have you authored a textbook on the subject of ventilation? >> yes, i have offered a large textbook on mechanical ventilation that's called the principles and practice of mechanical ventilation. >> so i'm showing the cover of your textbook here on the camera. is this the book you refer to? >> that is correct. >> 1500 pages? >> correct, 1500 pages, yeah. are you can live with the lancet medical journal pgh yes. the lancet is one of the top medical journals in the world. >> and that the lancet medical journal refer to this book as the bible on mechanical ventilation? >> yes, it is called the. >> have the author of the books
also? >> yes. >> roughly how many? >> i think eight or nine other books. >> and all related to respiration or respiratory failure? >> correct. pick their all in different aspects of the lungs. have you published articles and abstracts also? >> yes, i have. >> approximate how many of those. >> i lose count but i think i've published more than 750 probably or something like that. >> have you published in "the new england journal of medicine"? >> yes, i published several articles in "the new england journal of medicine." >> the journal of the american association. >> yes like why. >> of those the most respected medical journals in the world? >> are for clinical work, yes. >> had also held editorial positions at medical journal? >> yes, i was medical in chief of the journal called the american journal of -- critical care medicine so that is the
premier journal in the world for all lung disease. it's also the premier journal in the world for intensive care medicine and its it's the ol journal of the american thoracic society. >> have you taught and lectured outside of illinois and/or texas? >> yes. >> generally, where? >> i've lectured all around the world. i've lectured in more than 30 different countries around the world and probably vast majority of states within the united states. >> minnesota is one of the states and the united states. how about minnesota? >> i have lectured in minnesota. i have been in the mayo clinic several times as a lecturer. >> were you given an award from the mayo clinic? >> yes, i was given award in the mayo clinic and they give it out to one doctor every ten years, and it's only to one doctor. it doesn't matter what specialty so could be around neurosurgery,
gynecology, whatever. they just pick one person every ten years. >> and wasn't breathing in particular that you were recognized by the new clinic? >> no, just from my work as a research in clinical medicine. >> have you also published in basic science journals such as the journal of applied physiology? >> yes, i published a lot of work on basic science that wouldn't necessarily be directly related to medicine in the journal of applied physiology. >> the jurors may not be familiar with what physiology is as a science. could you gently explained at? >> physiology is basically how the body works. you want to know the signs about works. you want a deeper understanding of what really are the mechanisms that make the body does what it does. >> within the field of physiology is there a particur focus or interest you have? >> i am primarily interested in
breathing, in the bigger areas. so with breathing that would mean how the brain regulates your briefing, how the brain sends signals down to the muscles that control your breathing, your diaphragm, your rib cage, and then how you expand your chest and how you overcome forces within your chest like resistance within your chest and all the rest of it to get air moving in and out of your lungs, and then the particular forces that you generate in terms of the pressures within your chest that will enable breathing to occur with the ultimate purpose of getting oxygen in and getting rid of carbon dioxide. >> and do you consider this a part of the study of medicine? >> it's not quite as part of the study of medicine. it's really quite separate because it is more the basic physiology. so it is more in the realm of math and physics but then it is applied over because to be at
the doctor you need to have a good knowledge of science, but the science part is really separate from the medical part and it is to try to tone down on the site as best as possible. >> how long have you been working at respiratory physiology? >> since 1981. 40 years. >> and what exactly drew you to the physiology of breathing? >> because i was going into pulmonary -- at that stage i knew already directed, , i spent five years doing lung disease and i just wanted to really know how you breathe, and i wanted to come up with new knowledge. because everybody thought everybody knew everything how to breathe. i found it fun to learn new stuff. >> so doctor do you know of others kind in your field who have been studying respiratory physiology for 46 years? >> no. i mean, i know along the way but
i would know no more than a handful or less of people who are still doing physiology at the patient's bedside. >> after 46 years. >> so doctor, let's change subject and talk a little bit about your experience in working serving as an expert. to serve as an -- have you served as an expert witness before? >> yes, i have. >> what types of cases? >> practically all of them have been in medical malpractice, so i've done it for both the plaintiff, or the patient's site and i've done it for the defense, for the physicians side. >> have you ever been involved in a criminal case before? >> no. i've never been involved in a criminal case. >> have you testified in court before? >> i testified in court i don't keep track of the numbers i i suspect i've been in court like 50 times. >> would you tell the ladies and gentlemen, if you're getting
paid for your time in this case? >> no, i am not getting paid. >> and why is that? >> well, when i was asked to do the case i thought i might have some knowledge that would be helpful to explain how mr. floyd died. and since i've never done this type of work in this nature before, i decided i shouldn't be paid for it. >> so did you volunteer to the state of minnesota, or did the state of minnesota kali? >> the state of minnesota contacted me. >> what would you ask to do? >> i was asked to review the medical records related to the case. these were medical records from hennepin county. the number of interviews of people that were interviewed. i was given a long list of these comp and primarily it was related to looking at a large number of different videos. of course then the big part was
that he needed to read on the scientific background of all the various aspects related. >> all right. so let's talk about your opinions with respect to this case. have you form an opinion to reasonable degree of medical certainty on the cause of mr. floyd to death? >> yes, i have. >> would you please tell the jury what that opinion or opinions are? >> yes. mr. floyd died from a low level of oxygen. and this caused damage to his brain that we see, and it also caused aapa that caused his heart to stop. >> and by keeping a humane pulseless electrical activity? >> correct. it is a particular form of an abnormal key of the heart, and arrhythmia, particular form. >> is this what some persons might refer to as asphyxia?
>> yes. it has been called asphyxia. to me it's not -- really talk about a low level of oxygen. other people talk about hypoxia. that aching is just a latin term meaning a low level of oxygen. so all of this is just really other words for for a phenon that is a low level of oxygen. >> have you formed form a reasonable degree of medical certainty as to what the cause is or was a low level of oxygen in mr. floyd? >> yes, i have. >> would you tell us what that is? >> the cause of your low level of oxygen was shallow breathing, small breasts, small title functions that were not able to carry the air to his lungs down to the essential areas of the
lungs that get oxygen into the blood and get rid of the carbon dioxide. that's the bottom of the lungs. >> dr. tobin, using a short video you prepared to help you explain to the jurors, how oxygen gets into the lungs and the body, how we take in oxygen. >> yes. >> i'm going to show you what's been marked as exhibit 950. can you describe first what that is? >> so here we are looking at the lungs inside a body and we see here that you can see the windpipe up at the top the trachea and that splits into the bronchial tubes. and also you can see the diaphragm down at the bottom. and when the diaphragm contracts -- >> the jurors can't see it yet so i speedy i'm sorry, , terriby sorry. i apologize. >> i'm going to offer it, your
honor, exhibit 950. >> no objection. >> 950 is received. >> please proceed. we will display it so the jurors can see it. >> okay, so now we are looking come you can see the pink area down at the bottom. we see air going down through the windpipe and then proceeding down to the bronchial tubes and then it's going to continue down the bronchial tubes and will reach out to the air sacs which will be the alveoli. we are now seeing, moving down here and these are like the crêpe like structures down at the bottom and this is where all the action occurs. the oxygen goes across those air sacs and also the co2 goes across and it is expelled back it gets everything in a very rapid video. >> so then what happened in the case of mr. floyd that relates to the shallow breathing the
resulted in his low oxygen? >> so there are a number of forces that led to that. the size of his breath became so small, and so there's a series of forces higher up that are leading to that, and forces that are going to lead to the shallow breath are going to be that he is turned pro on the street, that he had the handcuffs in place combined with the street, then that he has acne on his neck, and that he has acne on his back and on the side -- he has a need -- all of these forces will result in the low tidal volume which gives you the shallow breath that we saw here. so the air will not be able to reach those air sacs we just saw in the video with oxygen is exchanged in the current dioxide is removed. >> is there a concept that the respiratory medicine field known
as dead space? >> yes, there is. >> how does that relate to mr. floyd? >> if you think of the video back all the way in tell you saw those clusters of grapes come where you saw the blood vessels surround the alveoli, everything up to their is dead space. as you are breathing in, your breathing through your nose, your mouth, goes down to the bronchial tubes, radiating out until it reaches the air sacs up to get to the air sacs. that's all dead space because the reason we call it is because no oxygen can get across those bronchial tubes. no carbon dioxide can get across it here the oxygen and the carbon dioxide, the only place that gets across is those great like structures. servicing in the lungs before that is dead space. >> so you mentioned several reasons for mr. floyd's low oxygen, at a just want to capture those for the jury. and then we'll talk about them.
on you mentioned one come handcuffs and the street. right? >> correct. >> you mentioned knee on the next. >> yes. >> sorry for my writing. you will know what i didn't get an a in school. the prone position? >> yes. >> and then the knee on the back, arm and side. were those the four? >> yes, these are the four. >> so we want to talk about each of these but before we do that might it be helpful for explaining your testimony to the
jury for them to see the relative positioning of the various offices on mr. floyd's body when he was on the ground? >> yes, i think i would be very helpful. >> did you assist in preparing an illustration to show the relative position of the officers on the ground? >> yes, i did. >> and let me show you what's been marked as exhibit 949. could you just tell us, just described generally for the record what it is. >> i mean, i watched the videos and certain segments of the videos hundreds of times, and it's very difficult to get an overall view of her everybody is positioned because you were seeing different videos from different angles. and so the artist has taken all the different videos here and he has combined into one moment in time. and you can see here, and also he would remove the police vehicles so you will get a better view. you're looking kind of that a
bird's-eye view of where mr. floyd is line and were the officers are positioned in relationship to mr. floyd. >> all right. so the purpose of this is a show the relative positions of the officers? >> correct. >> your honor, we offer exhibit 949. >> any objection? >> no, your honor. >> exhibit 949 is received. >> so what point in time if you told us this is at a particular point in time -- >> it is a particular point in time. i don't remember the exact minute, second off the top of my head. >> 8:21:44? >> yes. >> sound about right? >> yes. [inaudible]
>> okay. so let's walk through exhibit 949. doctor, tell us what we are seeing. >> you can see the car is being rotated. you are able to see officer chauvin. you can see officer kueng and officer laying down at his feet. use underneath mr. floyd and now the car is being rotated. now the car has been removed and so you are able to see how to positioned at different points in terms of with officer chauvin with his left knee on the neck, his right knee on mr. floyd arm and chest and then you can see
here officer laying hold of his legs, and then you can see officer kueng with his knee on his torso. >> so this represents a a snat in time as you told us. did the officers positions change over time as they were there on the ground? >> yes. the officers positions changed over time, and also the position of mr. floyd himself changed over time and these become relevant in how we evaluate everything. >> and was a a something to factored into your analysis? >> yes. >> did you consider where mr. chauvin's left knee was during the encounter? >> yes. for officer chauvin's left knee is virtually on the neck for the vast majority of the time. >> and when you say vast majority, are you able to --
>> more than 90% of the time in my calculations. there's certain times where it becomes difficult because you don't get a good view of where it is. so, for example, i know that officer chauvin's right knee is on his back he to 7% of the time. the reason i'm not able to say for the 43% is that it don't get a good view. other times i don't have a good view of exactly where it is. >> so did you focus on the first five minutes and two seconds? >> yes, i focus on the first five minutes and three seconds because that is up to the time that we see everything to brain injury. >> so if mr. chauvin's right knee was on his back from time to time and other times it was placed, where come in your observation? >> it was placed on his arm and
then rammed in to mr. floyd's left chest. so really whether you're making a distinction of whether the knee is on the chest, per se, or whether it's on the left arm and ramp in against the left chest. from the point of view of breathing, the effects are extremely similar. >> so let's turn to the number one on -- [inaudible] oh, yes. they are in the document. so i wanted to turn back to the notes, the number one here written down for the reasons you told us for floyd's mr. floyd's low oxygen, handcuffs in the street. talk about the first -- >> yes. >> could you first, dr. tobin,
tell us how these various mechanisms, the four that you discuss, handcuffs industry, knee on the neck, prone position, he on the neck, back, knee on the back, art and side, how does this mechanisms fall into your work and be the respiratory physiology or clinical medicine? >> they don't have an awful lot to do with clinical medicine, but they are directly related to my work in physiology. so in understanding the forces that the body has to cope with these become, these are crucial in terms of the various forces that are involved in physiology. >> so then turning to the first one, in handcuffs and the street, the very first one. what is the effect of the handcuffs in the context of what happened to mr. floyd? >> the handcuffs are extremely important to mr. floyd. but the handcuffs on their own,
just handcuffs per se are not that important. it must be the handcuffs combined with the street. and it's because of the position of the handcuffs at the back and how he is manipulated with the handcuffs by both officer shot shawmut and by officer kueng, have a manipulate the handcuffs, and they're pushing the handcuffs into his back and pushing them high. then on the other side you have the street. so the street is playing a crucial part because he is against a hard asphalt street. so the way they are pushing down on his handcuffs, combined with the street, his left side, and it is particularly the left side we see that, it's like the left side is in advice. it is totally being pushed in, squeezed in from each side, from the street at the bottom and then from the way that the handcuffs are manipulated.
it's not just the handcuffs. it's how the handcuffs are being held, how they're a being pushed, where they are being pushed that totally interfere with essential features of how we breathe. >> so mr. floyd then is pancaked between the pavement underneath him and forced on top of him? >> precisely. >> now, could you help us to explain how this mechanism, the handcuffs and the street, how does it explain the shallow breathing that you have described? >> so this gets back to how we breathe. and this is fairly simple. so the way we breathe, , we have two big muscles that help us with breathing. we had the diaphragm and we have the rib cage muscles. the diaphragm does about 70% of what we need for breathing, and about 30% of it comes from the rib cage. when the diaphragm contracts or
the rib cage contract, the expand the chest. and when you expand the chest then air flows in from outside and it is coming in, and that's all that happens on inspiration. but to expand the chest there's two crucial actions that have to happen and we referred to these by the terms pump handle and bucket handle. so bucket handle is simple. so if you have a regular bucket that you carry water with and you lift up the handle of the bucket, the handle comes up like this. and so when you contract your diaphragm you are performing a bucket handle movement of your under rib cage. so you can track your diaphragm like that, and each time as you inspire you can see it yourself. as you inspire each of you there in the jury, you see that you rib cage is going outwards like that. that's the bucket handle movement. the second movement that you
have is called the pump handle, and this reflects through an old water pump that would be in the yard for pumping out water. and so you have a handle at the top of the pump. you lift up the handle at the pump each time and the water comes out to spout at the bottom. so you would solely up, getting your container of water. so with that action your lifting up. this refers to the front to back movement of the chest wall. so with the pump handle your chest goes out with each breath. and so you can future self. as you take a deep breath you can see that front to back you are expanding your chest. the front to back expansion of your chest is what your pump handle. at the same time, you were doing both of them at the same time. at the same time you are doing that your chest is expanding
from two side, and that's with your bucket handle of these are occurring. these are vital but without that you can't breathe. if you don't have the bucket handle and the pump handle working there's no air going to get in there. >> doctor, do you have a photograph that you brought that would help to better understand the pump handle and bucket handle? >> yes. >> let me show you what has n marked as states exhibit 951. do you recognize what this photograph depicts? >> yes. >> is it an accurate portrayal of a certain incident? >> yes. >> would help to explain the test was? >> yes. is this an event that happened in england -- >> one moment. i need to offer, your honor. we offer exhibit 951. >> any objection?
>> objection is sustained. >> doctor come in this case were you able to absorb whether mr. floyd breathing was impacted by the handcuffs and the placement on the street? >> yes, yes, i was. >> what did you observe, dr. tobin? >> what i observed is particularly in terms of the hands of the police and the handcuffs, particularly on the left side. so they were forcing his left wrist up into his chest, forcing
it in tight against his chest, forcing it high up. and you had to keep in mind that the opposite side of this is the street. so he was being squashed between the two sides, and so this meant that he couldn't exert his pump handle. the street totally blocked his pump handle. there was no way he could do any front to back movement, and again the way they were pressing in on the back, it was absolutely no way that he could do any front to back movement. then in addition, because of the knee that was rammed in against the left side of his chest can sometimes the knee was down on the arm and against the chest, so this would have the same effect. so basically on the left side of his lungs, it was almost like a surgical -- was almost like a la surgeon had gone in and removed
the long. not quite but along those lines. so there was virtually very little opportunity for him to be able to get in the air to move into the left side of his chest. he was going to be totally dependent on what he would be able to do with the right side. >> have you selected any footage from the body-worn cameras that you feel depicts mr. floyd's struggles to breathe? >> yes. >> i'm going to show you what's been marked as state's exhibit 944. at first would you describe what it is? >> what you are seeing here is on -- >> dr. tobin, the doctors are not seen it yet. this is just for the record. >> oh, i'm sorry. they will not see this. i am describing what icing? >> for now, yes. >> that's fine. what i am seeing is that his left hand is being grabbed by
the police officers. so that's handcuffed left-hand and it is being pushed into his chest. so he is just that able to expand that. in addition, what i am seeing -- >> objection to foundation. >> i apologize. [inaudible] >> my misunderstanding. >> your honor, we will offer state's exhibit 944? >> no objection. >> 944 is received. >> now, dr. tobin, the jurors can see. >> i apologize. >> no note. it is quite all right. would you tell us what is a significant? >> what you can see is the yellow arrow you are able to see that the officer is holding mr. floyd's left-hand. he's holding get very firmly. there's a a very firm grasp o, and then mr. floyd's left-hand is being pushed in against his chest. also we are able to see just on
the side that officer chauvin's knee is coming in and that's compressing and against his side as well. so the ability to expand his left side here is enormously impaired. and also you are saying that the size of the chain between the right side and the left side is very short. so his whole left arm is also being pulled over, and so it is prevented him also from expanding the right side. .. >> trebek it was jammed down against his feet and so is playing a major roll in
preventing him from expanding. >> thank you if you could clear the screen. [inaudible]. >> you observed is mr. floyd struggled to brave. >> yes pretty. >> i'm going to show you exhibit 942. just identify it pretty. >> identify it. [inaudible]. >> thank you your honor. so do you or you do recognize this when they selected.
>> yes. >> we offer 942 pretty. >> no objection. 942 received. >> can you tell us about what the significance of this image of what we see here rated. >> what you are saying is different of the two images but the right together. if you look on the left side, you see his finger, is pushing against his feet. you also see the officers around his left hand, and you can see the left hand cuffed as we discussed, you're saying a more clear view here, how it's rammed into the back of his back. there's just no way that he would be able to expand. with the left image, you see the finger and then over on the right image, you see is knuckle against entire. and most people, this just does
not look terribly significance but to his physiologist, this is an extraordinary thing because because this tells you that he has used his resources and is now literally trying to brave with his fingers and knuckles read because when you begin to breathe, you begin to brave and rib cage in your diaphragm and the next thing that you recruit after that with the big muscle in your neck. and when those are wasted up, then you are relying on these types of muscles like your fingers to try to stabilize your whole right side because he is totally dependent on getting air into the right side. so is using his fingers and his knuckles against the street to try to crank up the right side of his chest, this is his only way to try to get air into the right long. >> doctor, he showing you exhibit 938.
is this related to series of photographs and images. >> yes. >> we offer exhibit 938. >> received. >> the doctor tell us what we see here in exhibit 938 pretty. >> the top panel is the same as the bottom one, the bottom is just the blowup of what use being on the top. and the focus on the left side is his shoulder and again, as i mentioned when you have difficulty breathing, you begin with your diaphragm from the rib cage and you go on to the assessment muscles and then one of the very last muscles that you will use his york shoulder. you don't really use your shoulder for breathing but if you look here on the left side,
the shoulder is extremely prominent so this is the image that we would call sculpting up the shoulder muscle. and you are saying them standing out prominently. at this point in the left-hand side, he is taking a breath and and using his shoulder to try to get a breath and. and then on the right side, you see between the breath where he is relaxing, not breathing out. the two of them are shown the mark on the left. but you have to realize that the shoulder, the very ineffective way of breathing because at that stage, the chest is also expanded so when you contract your shoulder, because the chest underlying it is so expended, get very very little air in it, it is very poor way of breathing it but it is what you have to do put everything else has failed, when your rate in the extreme. you would call on the use of the shoulder to try to bra.
>> so let's talk about number two, the knee on the neck. >> and explained why the knee in the neck is so significant. >> the knee in the neck is extremely important because it is going to contribute the air getting and through the passageway. >> so as possible doctor to demonstrate the anatomy lesson. and it may be relevant printed. >> to understand the knee on the neck, you need to examine your own next, all of you here in the jury, like i am doing now. so the first thing is that if you put your index and thumb,
you will find your adams apple then you can find the adam's apple is a very sturdy structure because it surrounded by cartledge and it protects the voicebox, the layer next, the sanction to. [inaudible]. so any amount of compression on the adams apple is not going to compress it. this is an extremely strong sturdy structure. it will be compressed by a knee on the neck. then you go down from adams apple new fee of those bumps beneath that and these are the cartilage. on your trachea, so this is your windpipe here. so again, because of the cartilage there in the knee in the front of that part is not going to cause compression. but then bring your finger up to the top of your adam's apple and up at the top of your adam's apple, you are now directly over
that hypothalamus and that is a crucial area in mr. george floyd in this here is where the located on your surface anatomy. >> so why is that important for understanding this case pretty. >> the hypo thermoses very important for understanding this case for a number of reasons because it is so vulnerable, because it has no cartilage around and it's going to be an area that is compressed, it's an extremely small to breathe through and becomes very important for being able to completely brave through. >> doctor want to show you what exhibit 935 and 937. could you identify just for the record tell us.
>> i am looking at 937 which is that both of us. and the other is with point pretty. >> and do these two images fairly and accurately depict that pretty. >> they do pretty. >> 935 and 937 offered. >> 935937 are received read. >> can we show them to the jury. doctor using exhibit sign 37 and 935, can you help us to better understand it what it is what it does. >> what you are looking at here, so here, where i have drawn in red is the top of your tongue. that is the tongue then above it
is nifty space and then above that is the top of it so that orientation you there. and then the tongue it comes down along here in the critical structure in this case because the active speech becomes very important, how you would be able to speak in all these different things. so the structure that uses this are the vocal chords here. the voicebox and the layer neck. then you have a little area here, a little sliver and that comes back to prevent food going the wrong way when we are swallowing because we use this both for stalling, eating and use it also for breathing so when we are breathing it, there is going to come into your nose and your mouth goes on down to it and then to the vocal cords and into the wind pipe and trachea and you go on down into
the lungs wears when you are swallowing that traps would prevent the food going into the air passages and directed into the back of the esophagus. and the area of the hypopharynx is exactly from the base of it, the first yellow arrow down to the second yellow arrow which is that a layer next and that's a small area, that is the part of the hypopharynx. >> and receipt 935. >> so we know that the cross-section of area of the hypopharynx, i have it here as 199 - 303 and obviously difficult to remember those type of things but in fact, right in the middle of this would be the size of the dime sewing time is basically the size of what the hypopharynx is in it tells you
how small and how vulnerable this area is so if it's going to be decreasing in size. it would be a very tiny area. >> so why is the hypopharynx important in the case of mr. george floyd pretty. >> because the hypopharynx is going to be the area that would be vulnerable to intrusion from the knee on the neck but in addition, the hypopharynx has another aspect and that is the hypopharynx is also controlled by the size of your lungs. and as your lungs expand, you increase the size of the hypopharynx with every breath so there's a regulation of that that is going on. >> was derek chauvin having pressure on george floyd pretty. >> it varies from time to time. >> are you able to tell us that
if mr. derek chauvin had put his weight directly, his full weight on mr. george floyd's neck, are you able to tell us what impact would affect on mr. george floyd. >> if officer derek chauvin had placed his knee directly on the hypopharynx, just that area of the dime, and it never varied from their in a kind of came in on like a bull's-eye in that area than you would expect this area would become totally excluded, but he varied the position and also george floyd varied the position of his had an officer derek chauvin also buried the position of his knee. so varied over time. >> had become totally occluded, then what pretty. >> thin and fit had become totally occluded, within seconds he would drop the level of oxygen to a level that would be
oxygen deprivation in the body resulting in either a seizure or a heart attack, one of the other. >> given in the photograph taken footage at the scene that would help the jury understand your point pretty. >> yes. >> exhibit 941. and this is derived from exhibit already in evidence. do you recognize this photograph of 941 pretty. >> yes. it. >> offer exhibit 941. >> 941 is received. doctor, the ladies and gentlemen of the jury, what it is you me to convey here in exhibit 941. >> so if you are looking on the left, look at that first so if
you stick your finger in your ear and you draw the line from the finger in your air going down to the first part of your body your spinal column coming can get a line going on in your looking at that x. and that is what i have gone here with the yellow dot nine. and so if you look here on the first slide, you see that mr. george floyd knows that is faces directly facedown on the street. it's not at any angle, so the next thing you then look at the slide, on your own neck, and now put your hand at the back of her neck, and you feel the bottom of your school and so where this goal the bun of the school and is in any come down from that and you'll find any put the whole palm of your hand.
[inaudible]. [inaudible]. >> the witnesses as to do certain things, you're not required. more in terms of if you were to do that in the few wish to do it, that is your choice. you are not required to do anything when is has instructed you to do. >> thank you your honor. doctor, we could go back to where you are explaining the anatomy of the back or the base of the skull. >> so as i am putting my hand here at the back of my neck, and i am feeling the tip of my skull and then in bringing, hannah, an extremely, the nuclear ligament and is almost, as i put the fulm
of my hand on this ligament, is almost like would. and is so strong of the ligament. and that is what you are saying the knee is being over on the left-hand side. so with the knee directly over this ligament, it can cause no abstract and hundreds of section. this is such a dense ligament. and that is what you are seeing if you are sing this where with a yellow triangle of, sorry the diagonal, that is the bulk of the officers derek chauvin is above that yellow line. and the second thing, separate from is this others like community that mr. george floyd has his face to the street because he is using his face here, to crank up his chest. his actually using his forehead in his nose and is ten as a way
of trying to help them get air into the right side of his chest, that is another way to crank up his chest pretty. >> have you can't consent to what we see in the photograph on the right in exhibit 941. >> right hand side, you can see orientation now of mr. george floyd has changed and also you can see the position of officer derek chauvin's and he changed, it has come down below the yellow diagonal. in this position, there's going to be far greater compression of the hypopharynx in this region here compared with what you are saying on the left side. on the left side, there is no compression of the hypopharynx but on the right side, and if you watch the videos over time, you will see there is a variation of time as to where exactly is the location of mr. george floyd and and where is the location of officer derek
chauvin knee. >> and in the photograph on the right, then he is exerting greater force on the hypopharynx. >> correct. >> is it possible to capulet the amount of force. >> yes it is. we can calculate the amount of force based on the weight of officer derek chauvin and his body weight taken into account how much he weighs and the gear that he carries and then also you have to remove out the weight of his shinbone and his boot, subtracting out all of these and then you can calculate the weight. >> and also the changes for narrowing in the space people have to breathe through. >> yes you can separately. would this be a can to rethink
for a small opening like a straw. >> isn't good at. when you have to breathe through a narrow passageway, it is like breathing through a drinking straw, but it's much worse than that because drip breathing through drinking straw, is somewhat unpleasant but not that unpleasant. >> so as a space narrows, is a more difficult than to break pretty. >> enormously more difficult and we know that. >> to physics, is that also something that can be calculated. >> yes, i can. >> and the calculation, would it be specific per se to george floyd. >> know it what it. it would be for anybody, we know in terms of what is happened of, this level of narrowing, but happen to everybody. >> can you please explain to the jury what those calculations what a show about the effects of the narrowing on the airway. >> yes.
[inaudible]. >> 939 and 940 are received. >> so i will look at exhibit 940. doctor tobin, described as for us pretty. >> so this is a experiment. and what it is looking at is what is the effort to brief, that is what is shown along the y axis of the straw and then it is with the narrowing so with the very bottom one with the white triangle, the lowest curve. that is normal, there is no narrowing so we see the flow very raise and shown in red is the normal flow rate and a 46 -year-old man and we can see the work that has done. and if you look at the normal ones and then you look at 60 percent airway narrowing and this is much more narrow than breathing three straw, and you can see there is really no
bigger increase in the effort to break, different from what is in terms of normal. but then if you get 85 percent narrowing, now you see that the effort to breathe increases seven and a half times compared with no narrowing and so you are seeing a huge increase in the work that is required, it becomes far more difficult to breathe is the narrowing becomes more narrow. >> let's look at exhibit 939 dr. tobin. >> this is the science behind it. this is just the equation in physics that tells you how that works. and the key thing is when you look at an equation like this, form means under me as a physiologist, i focus on the sign of the restriction that tells me here when i see a
square sign at the top and it is below the level on the equation, it is the denominator. i know with that, that you're going to be for fine for a period of time and then suddenly you will be increased enormously, the exponentially increase rated that's exactly what we see on the experiment that was done, we are seeing is really nothing happening at 60, nothing much but then it 85 percent, it suddenly takes off and if you had beyond 85 percent, it would be even more so. so based on the formula here, you can tell that as you are narrowing and narrowing, the effort to breathe is going to become extraordinarily high and in some stage, so unsustainable. you will just not be able to do it. >> so in this case, the case of mr. george floyd, the narrowing was of the hypopharynx.
>> yes. it was the hypopharynx. >> did mr. derek chauvin on george floyd's neck because this. >> yes. >> said given the changes that you observed in mr. derek chauvin's name, mr. george floyd over time, where any of those changes significant from the standpoint of placing pressure on the hypopharynx. >> yes. >> let's look at exhibit 947. your honor, we would offer exhibit 947, which was taken from exhibit 15. >> 947 is received.
>> tell us what we see here in exhibit 947. >> this is the orientation of officer derek chauvin, is body is quite erect here, but in particular what you are saying is that the toe of his boot is no longer touching the ground. this means that all of his body weight is being directed down at mr. george floyd's neck. because, in any of the calculations, i excluded the effect of his leg and his shoe because some of it was touching the ground. but here you can see that none of it is touching the ground, so we are taking it half his body weight plus the weight of his gear and all of that is coming down directly down on mr. george floyd's neck. >> on the show you exhibit 943.
did you assist in preparing this exhibit. >> yes. >> would help explain your testimony. >> yes. >> we offer exhibit 942. >> received. >> 943 is received. >> could you clear the screen your honor. thank you. >> dr. tobin are we sing here. >> have his body weight plus have his gear weight is coming out, that is pretty 1.5 pounds is coming down directly on mr. george floyd's neck. >> is not always eat. >> the reason that we are saying that is because the total is off the ground and there's nobody weight sitting back. he is not conquering back, so
everything is directly down on his knee, and in the space is sharon and it is toe in his boot is playing no contribution. >> and is a time when mr. derek chauvin's left knee was on the back of george floyd's neck and when was that pretty. >> when his knees on the back, that is a separate force, the same force but it is compressing in a different area, it is compressing inside of his chest. >> what about the time when mr. george floyd would've been having his face smashed directly to the pavement. >> when is faces into the pavement, at that time it like one of the ones that i should do, coming down in the new, there's a huge weight but he will be compressing the hypopharynx at the time and that is happening. so all of these different forces, there's some what complex in terms of how they are
interacting but they all coming to the same point. >> pay particular attention to almost the first five minutes in this route three seconds of this on the ground. >> yes, sir. >> how would you compare mr. george floyd's oxygen level that mr. derek chauvin was on top of him that first five minutes. >> we know that the oxygen levels were enough to keep his brain alive and the reason we know that is because he continued to speak over that time. we know that he made various vocal sounds for four minutes and 51 seconds from the time that the knee is placed on the neck. and that is telling us that he speaking but the big thing is because he can't speak without a brain. so we know there's oxygen getting to his brain for whenever he is making an attempt
you are focused on the first five minutes and three seconds in particular that mr. derek chauvin was applying his weight to mr. george floyd's neck. >> hi why was the time. after the five minutes and seconds afterwards pretty. >> because at that point, where he extended his leg, that we see happening at the point that we see that happening, is at 2421. that's when he suffered brain injury, and we can tell from the movement is of his legs the level of oxygen in his brain is caused we call a seizure type of activity. their medical terms but it basically means that he has kicked out his legs and an
extension form, that he has straightened out his legs and that is something that we see as physicians and patients they suffer brain injury as a result of a low level of oxygen. >> will talk about that more in a moment. dr. tobin but is a significant whether mr. derek chauvin moved his leg off of george floyd after george floyd is unconscious pretty. >> no. the movement happened around a different time but obviously, the key thing is everything up to the time that we see the hypopharynx, that is occurring. with the officer derek chauvin moved his knee after that really is not quite have any material impact on the case. >> we can help ladies and gentlemen of the jury understand that if esther derek chauvin is applying pressure on the side of the neck as we see here in
exhibit 943, does it translate into narrowing of the hypopharynx. >> is going to depend on what is the orientation of officer derek chauvin body and is orientation of his leg and then also in particular into what is the orientation of mr. george floyd and where exactly is the orientation of george floyd. because it is the ligaments, and is underneath officer derek chauvin's knee, there's going to be various compression of the hypopharynx in this region and then if it moves to the side, and officer derek chauvin weight is coming down on the side of mr. george floyd's neck, then you get a huge compression of the hypopharynx. >> again looking at exhibit 943 and focusing on the first five minutes. it was his knee overarching
really on the side or on the back. >> for the first five minutes, the left knee is on the neck virtually all of the time in the right knee by my calculations, the right knee is on his back 6. in the reasons that i can say that is not a hundred percent is because most of that of the time, i don't get a good view of the camera, they move around. the body camera so i cannot see it but for that period of time, the crucial period of time, that the five minutes and three seconds, i can see the officer derek chauvin knee on his back for over 57 percent of the time. >> let's talk about the third mechanism of the prone position. with george floyd being placed in his prone position and also
have an impact on the narrowing of the hypopharynx. >> yes facing him on the prone position has several different effects but particularly, it also causes narrowing of the hypopharynx among other things that the prone position does. >> is there concept of physiology referred to as long files pretty. >> yes there are. >> what is that, what is not referred to. >> is just the way we long specialist, we measure how the size of long indifferent patients. and we quantify out in different areas, what level of the long there is, whether it is different segments of the long behave in different ways. >> do you have an illustration that you brought to help us better understand the concept pretty. >> yes. >> i'm going to show you exhibit 929 have you first identify it.
>> i am identifying this pretty this is well it shows you loan functions and it shows you. [inaudible]. >> is an inaccurate illustration of lung function and title - >> yes it is. >> i offered exhibit 929 pretty. >> is there any objection. >> 929 is received. >> so we can get started again. do i go ahead and describe this. yes. [inaudible]. we are getting into a bad habit pretty could you ask the question again please. i forgot it pretty. >> thank you your honor, i'm just going to ask you dr. tobin if you would explain to us what we see in exhibit 929 pretty. >> we are looking here the lungs inside of the chest of the chest is great and we see the long
inside and around the space. and we are saying that as we were looking at this going in and out it generates volume and it showed as a waveform down at the bottom. and so that is what happens in somebody with what would regular people. >> let me see if we can get our title volume. >> so here you can see that the chest is expanding like right in the front here, the actions of the chest. then with each breath you can see air going into the lungs that produces the size of breath. so this is the title volume. an inner exhalation is going backup. that was the tidal volume. >> standard for normal size of breath pretty.
>> yes there is an virtually all adults, people, it is about 400 cc, the size of the tidal printed the same for men and women and for teenagers and grandparents. >> so can lung volumes be calculated that pretty. >> yes then you can calculate further additions. >> did you actually do a calculation for mr. george floyd lung volume pretty. >> is a calculated how does lung volume precisely based on his age, his and his height. ... ...
>> so with using this be helpful to explain her testimony? >> yes what. >> your honor, i want to offer exhibit 930. >> any objection? >> none, your honor. >> 930 is received. >> these are the lung volumes in mr. floyd while he is sitting on the sidewalk, and the volume will be focusing on is the elv, the in expiratory lung volume. that becomes crucially important in understanding what happened to mr. floyd. i calculate out his elv to be 3840 and that's what it is shown there by the horizontal -- [inaudible] sitting on top of that it is the size of each breath and then underneath is the residual volume. the residual volume is when you
blow all the out of your long and that's your finished blowing, you can't looking out. that's the area that is still left inside your chest is the residual volume. that in mr. floyd is to leaders and 300 cc. -- two two leaders. that is included in the eelv. eelv is everything below that horizontal purple line. the eelv sitting upright is 3840. we also see -- >> if i could stop you for just one second. to help us understand better the mr. end expiratory lung volume, eelv, would that be, referred to as oxygen reserves? >> that's also where your main oxygen stores are in the body. they are contained within your eelv. this is where you store your oxygen reserves.
>> so for the ladies and gentlemen of the jury , it's true that not all the air you breathe it is exhaled out? >> no. i mean, the eelv is basically the volume that is in your lung in between each breath. so when you are breathing in and out, when you're between the next breath, what is in your lung is your eelv. >> and the residual balls you, rv, is that also residual oxygen the body can you? >> yes. >> so the oxygen reserves you have are included in the eelv and obviously a subset of the eelv is a residual volume. all below the purple horizontal come all below your tidal volume is your oxygen reserves. >> so then can you explain your tax relations for mr. floyd's lungs? >> so here we see based on his
age come his sex and his height we are seeing exactly that is eelv sitting upright is 3840, and we see is residual volume is 2300. >> and again if the matter their he's taking in in tidal volume would be the same as anyone else? >> right and that is the 400 at the top. that is a tidal volume and that's the same as for anybody. >> 400 cc? >> correct. >> cubic centimeters? >> cubic centimeters, or millimeters or oh however you want to put it. >> the oxygen graph is on the side? >> yes. >> what does that depict? >> the level of oxygen with anybody varies with age and this is exactly the level of oxygen you expect in a 46-year-old man. so. so it is a po2, the level of oxygen measured in pressure of oxygen if you do an arterial
blood glass were somebody sticks of needle in your risk, took out a sample of arterial blood,, that's a level of oxygen they will find, 89 millimeters of mercury is how come is the units we use when we describe levels of oxygen. >> you told us that mr. floyd being in the prone position served to narrow the hypopharynx or decrease the vibe of oxygen in the long? >> bright. it had multiple effects including those two. >> why is that? >> because that eelv is very important in terms of obviously it's where we store the oxygen but as well is that it has an effect on the upper airway. so when you breathe then you don't notice it, as you are expanding your lungs you're aware of expanding your lungs but at the same time the size of your hypopharynx also widens out because there's attraction forces that are occurring
between. it's just part of normal breathing that as you inhale you expand your lungs but you also expand that little area that you have the air has to go down through. so that is influenced by the size of the eelv. likewise when the eelv gets less, then the size of the opening of the hypopharynx also get less. it's going to collapse down. as your eelv goes down. >> did you actually calculate the reduction in lung volume for mr. floyd due to the proposition? >> yes, i did. >> could i show dr. tobin exhibit 927? doctor, is exhibit 927 the calculation that i am referring to? >> yes. >> your honor, i offer exhibit 927. >> any objection? [inaudible]
ninety-seven? >> yes. >> -- 927? no objection. >> 927 is received. >> so dr. tobin, tell us what we are seeing here in exhibit 927 as relates to mr. floyd in the prone position. >> you were seeing it smaller when you're placed facedown. and so you're getting a decrease in the volume and that is occurring because in part let's say you're lying flat into bed with your her face in the pillow if you are laying prone facedown. you are no longer going to be able to use your bucket handle
action. so your lungs are going to get smaller. you are also going to greater difficulty in using your bucket handle action, less so than the pump handle. and then as well as that as you lay facedown your belly is going to rise up into your chest and so your diaphragm rises. so the lungs get smaller and that is what we see here. so if anybody who is turned prone you see that the lung volumes on average go down by about 24% by simply turning them prone. so with that when you're getting the small involved into getting less reserves and you're also going to affect the hypopharynx. >> so if the lung size go down 24% come to the oxygen stores also down 24%? >> the oxygen stores will go down by 24% 24% as well. once you have less volume inside your lungs, your oxygen reserves are going to go down
proportionately. >> is absolute when a 4%? >> no. i mean, again in physiology the way we do things is look at what is the average change that happens when we do experiments. but in biology there's always a certain amount of biological variation. and so there's always going to be something like us to do for% variation you are going to see around these numbers, but -- two the 4% we speak of the average change that is occurring. >> so is the 24% reduction significant in the case of mr. floyd? >> yes, it is extremely important because again because of the factors that we are dealing with. we are seeing here that with the reduction in the eelv just from the prone, decreasing the oxygen reserves, we are also affecting the size of the opening of the hypopharynx because as a eelv
goes down your getting a proportional reduction in the size of that. and in addition when you are turned prone like this your work of breathing goes up because of stiffness of your lungs changes and the stiffness of your chest wall changes. so the person has to do more effort to breathe in that position. >> so the hypopharynx is linked to the size of the loan that is the size of the hypopharynx? >> yes your doctor, maybe you can help us understand this. is it true that some person suffering from covid actually treated in the prone position? >> absolutely. >> why is that? >> it's a different scenario but, i mean, in any patients with pneumonia taken with covid but receiving any patients with pneumonia, when you turn them prone it can help. the problem is if the have pneumonia they have bad matching
between blood vessels going through the lungs and the air sacs. we saw the movie at the beginning resolve the alveoli and you saw all those blood vessels surrounding the bunch of grapes. in people who have pneumonia, covid, whatever, that matching is going to be very bad and that's what leads to the worst oxygenation in those patients. if you flip those patients prone, some of them will show no improvement but a substantial number of them, the matching will get better between the blood vessels and the air sacs. you can't predict ahead of time until you turn the patient prone come you will not know which ones would do better but some of them do. and so this is why prone has been very valuable in patients with covid but that is in people with pneumonia, just does not apply to people with normal
lungs. it's not happening. >> dr. tobin, also a lot of people sleep in the prone position. >> yes. >> is that dangerous? >> no. because again for the average person you have so much reserves. so, i mean, for a drop of 24% for you is not going to have any impact because you have a huge amount of reserve it's not going to matter. but if somebody who drops the lung volume by 24% and then that person is going to have to cope with a knee on the neck and is going to have to cope with having the arms pushed up and being unable to move the left lung, then it's a whole different kettle of fish. >> thank you, doctor. so have you covered the third mechanism the prone position? >> yes. >> then let's talk about the fourth. which is the knee on the back arm or side.
>> yes. >> now, if we bring to mind mr. chauvin's right knee on mr. floyd back or left side -- let me ask this. forget that question. does it matter whether the right knee was on mr. floyd back or left arm or his site. >> was no. it's really all about into the same. because we talking again back to the bucket handle and the pump handle. so whether it's on the back or rand in against the side and down on the arm, all of these are just going to markedly impair your ability to be able to move your chest with your bucket handle and your pump handle. you just can't do it. it's all rammed in. also the whole time in this case
you have to constantly keep in mind that this is taking place on the street. the street is playing a huge part because it's coming in in the front and totally preventing every action happening on the front. >> did that influence mr. floyd's oxygen reserves? >> yes, they are going down. once the eelv goes down every proportionate decrease you are seeing in the eelv you are seeing the same proportionate decrease in the oxygen stores. >> were you able to calculate what that influence was? >> yes. >> i want to share what is marked as exhibit 932. and ask you, dr. tobin, does this reflect the calculations that he did? >> yes, this does. but now you see -- >> one moment, doctor. your honor, i want to, i offer exhibit 93232. >> any objection?
>> no objection. >> 932 is received. >> now doctor please tell us what we see in 932. >> what you were seeing now is that networks no longer just prone. now you have the knee on the back in addition or the knee on the side. and so it is, this is going to her the compressed down the eelv. so here you are seeing that the eelv is now being really squashed down. so by the combination of turning him prone and also having the knee on the back you are seeing a 43% reduction in the eelv, which means that there's also a 43% reduction in his oxygen reserves, which means there is also a huge reduction in the size of the hypopharynx. because this is directly linked to the hypopharynx, and you will
see how this is linked. and so when you decrease the size of the eelv, that's going to cause it. and an additional effect is that your work of breathing goes up because when you are turned prone and with the knee on the back, now the work that mr. floyd has to perform becomes huge because he has to come with each breath he has to try and fight against the street. yester try to fight with the small volumes that he has and then he has to try and lift up the officers in the with each breath, and also remember yester try and also lift up the effect of the other officer pumping in his arm with a handcuffed arm. they are pushing it into his chest. so yesterday call these efforts to try and breathe against that. >> so doctor when you tell us about a 43% reduction, 24% of that is just being in the prone
position? >> correct. >> the of the 19% is the contribution of the knee on the neck? >> exactly. the other 19% -- so 24% from being prone and another 19% coming from the knee on the back. >> just so we're clear back. >> just so we're clear for the jury had his this translate into difficulty in breathing? >> again i did calculations of this, and basically you're looking at more than a threefold increase in the work of breathing, in terms of just from the effect of nothing else. that's even leaving out the effect of the knee on the neck. just some look at what's happening within the chest. so there's a huge increase in the work that mr. floyd was performing just to try and cope with what was happening below the neck, leaving aside what is happening above the neck. >> doctor, i want to show you exhibit 922-926.
and that you have a chance to see them i want you first to identify just what we are seeing in those before we show to the jury. >> yes, i identify. >> tell us please what it is for the record. >> we are looking at the effect of the lungs on the hypopharynx beginning with mr. floyd sitting on the sidewalk. >> your honor, offer exhibit 922 through 926. >> any objection? [inaudible] [inaudible conversations] >> no objection.
>> 920 through through nine it is my sixth inclusive are received. >> doctor, if you walk us through these help us understand a link of the hypopharynx in the case of mr. floyd. >> right. before you look at the hypopharynx just looked down at the lungs and you see that the lungs as you'd expect their expanding with each breath. you see the type am going to pick you can see the pump handle action, the lungs are getting bigger, the back then you see that exactly as the lungs are expanding, if you focus up in the yellow box and then the yellow box is enlarged over on the right side. and you can see that as you inspire, the size of the hypopharynx is also inspired come is enlarging. so you were seeing both of these happening, so it is the effect of the of the lung volume, how it influences the opening of the hypopharynx. and this is sitting on the
sidewalk. >> so looking at exhibit 922 what do we see here now in the prone position? >> so now we see mr. floyd after he is turned prone and now we can see the lungs are smaller than they were because they fall as we know when you turn prone. and then you also see now that the area, the hypopharynx, is further narrowed because the lungs as they get smaller they have less effect in keeping it t open. and so that gets smaller. >> okay. >> and then we have the knee on the back, and now we with the knee on the back, then the lungs become further reduced like i showed you for the precise calculations of the volumes and now you see here is the size of the hypopharynx further is shrunk as result of it. so the opening through the hypopharynx is impacted by the
knee on the back. >> and if we compare them altogether all three -- >> you were seeing than her altogether. on the left is sitting on the sidewalk, then just the effect of prone and then the effect of prone with the back compression. you can see the arrow is pointing out to you on the first one what is the hypopharynx right, that area, and with -- you can see it is expanding when he is sitting down. and then when he is prone and when he is prone with the back compression. you are seeing that the area of expansion is skating smaller, as exactly as what you would expect to happen. >> going back to mr. floyd salon
volumes, dr. tobin, is there a point in time when you determined -- mr. floyd's lung volumes -- where mr. floyd does not have enough oxygen in his stores remain conscious? >> yes, there is. >> and when was that? >> the time in terms of the loss of consciousness was 24:53. we can have precise in terms of where the absence of consciousness occurs. >> and can you tell bifacial features? >> i mean, this is something i do not as a physiologist but as an icu doctor. we are always looking at facial features to be able to tell how conscious somebody is. and we can tell how your eyes for how you move with the n your face, and that you will be able to tell is the person conscious or unconscious. it's a very important sign in patience as we are taking care of them, to be able to monitor that and in the primary way we
monitor it is by speculates i would've done this millions of times. >> do you know, dr. tobin, what is oxygen level would've been at the time he went unconscious? >> yes, we also know that at the time you get somebody who is in the situation who is at risk, we know that the moment at which you lose consciousness the level of oxygen in your blood will be 36 here at the number that is associated based on very hard scientific data telling us that. >> and against the normal level of oxygen was -- >> in mr. floyd was 89, and a 46-year-old man you man you expect the normal level of oxygen is 89. the level at which you would have an absence of consciousness then would be 36. >> doctor, i want to shoot exhibit 928. -- show you.
if we could clear the screen, your honor. first for the record before we show this to the jury can you just identify what is exhibit 928? >> we look at the effects on mr. floyd's oxygen as result of all the various maneuvers that are being done to him. >> your honor, i i offer exhit 928. >> any objection? >> none your honor. >> 928 is received. >> so tell us, dr. tobin, what we see here in exhibit nine under 28? >> we are looking at, i mean whitney kent the level of oxygen when i saw it, begin with a level of oxygen of 89, and then we see that it falls down to 36. the slide is looking a bit different than what i saw before. so here you see that the level
of oxygen forehand is 89 and then at the point when we notice the lack of consciousness in his face that the level of oxygen dropped down to 36. so that tells you, that tells you for the time of the loss of consciousness. and we know it continues from their, from the time that he stopped breathing, which is 20:25:16 and then i calculated out that from there on that you can calculate based on a given very rigorous science when the level of oxygen would have gone down to zero. but this first one we are looking at the level, the loss of consciousness at 36, and
that's happening at 20:24:53 and we are able to tell that by looking at his face. >> and 20:24:53 is 8:24 p.m. and 53 seconds? >> correct. >> was a point in time when mr. floyd no longer had any oxygen left in his body? >> there is because once again when he stops breathing at 20:25:16 then it would take another 25 seconds for the level of oxygen to go down to zero. at that point he would have enough oxygen left in his entire body. >> doctor doctor, i want tt exhibit 931. >> okay. >> and ask you first if you adjust tell us what it depicts before we show it to the jury. >> yes, that is it showing exactly. >> what you receipt in 931?
>> so what we are seeing in 9:30 one is that his level of oxygen has got all the way down to zero. >> so we will show this to the jury but first let me move to admit exhibit 931. >> any objection? >> none, your honor. >> 931 is received. >> dr. tobin would you explain what we see in exhibit 931? >> we are seeing the love of oxygen has gone down to zero, that there is at that point does not an ounce of oxygen left in his body. and again this is totally calm you can figure this out with very precise science looking at once somebody stops breathing what would be the level of decline oxygen how long it will take to reach zero. so we see here that he reaches a level of zero of oxygen at 20:25:41 ansell at that point does not an ounce of oxygen left in his body in his entire body
at 20:25:41. >> so was the knees and lifted off his neck at the point there was no oxygen in his body? >> no. than need be made on the neck for another three minutes and two seconds after we reached the point where there's not an ounce of oxygen left in the body. >> thank you, doctor. are you aware of a study suggesting that putting someone in the prone position and putting a weight on the back is not dangerous pgh yes i am aware of these studies. they largely come out from san diego from the group of dr. chan and his colleagues. >> are you able to generally characterize the nature of the study for the jury? >> the bottom line is they are highly misleading. >> are they relevant to the analysis you have just given to the jury this morning?
>> no, they are not relevant to the analysis we have gone through this might. >> help us understand why. >> okay. the problem is in these particular studies, i mean i don't know how many and total but could be close to ten of them, and where they take people -- first of all that take perfectly healthy volunteers here if they bring them into the physiology lab and they lay thin flat input of matt on them which is different from the street and they put weight on top of them so the weights could be led weight in bags or in many of them they use kind of the barbells that you see in the gym like an olympic wheel that you see in the gym for weightlifting, and they place those on the back of the subjects and a measure various lung volumes it's a typically they will measure what we call maximum ventilation. these are specific types of lung
function tests that you don't need to bother with but they are showing a decrease in lung availability of around 35%. that's a substantial decrease in your lung volumes that you are finding. and then they conclude in virtually all of their studies that that level of decrease in lung volume doesn't matter because there's no change in the level of oxygen. and so, therefore, it's not clinically relevant. the problem is in doing a study like that oxygen is the exact wrong arctic to be using in a study like this. what they needed to do is continue to measure out the changes in lung volume like the eelv showing what happens to this. oxygen will only fall at the very end. it's an extremely insensitive measure your it's very important but it's very insensitive to know that stuff is going back inside the body. that's going to be a very late
event. and so for their concluding of this -- >> do have another question? [inaudible] >> so to help us better understand, dr. tobin, are these studies measuring the diminution or decrease in the oxygen reserve, the eelv? >> no, they are not. >> i want to show you what is marked as exhibit 948. and does exhibit 948-point to one of the studies that you were referring to? >> yes, it does. >> would it be helpful to use this like to explain your testimony? >> yes, it would. >> your honor, we would offer exhibit 948.
>> any objection? >> none, your honor. >> 948 is received. >> so look at the slide, dr. tobin, what does this tell us in terms of, for example, the surface area that is involved of the weight on the back. >> so if you look at the subjects back you can see here that there are four weights out of the gym that a place on the back of the subject. and the big wheel out at, and olympic plate come is going to have a diameter of 17.5 inches. see you can measure the cross-section of very of that is going to be 240 square inches. the trouble is that when officers kneel on the back of a suspect they don't place and olympic wheel on their back. they place their knee and so the sectional area of the knee is 24 square inches, which is one-tenth of the area of the big
bells you are looking at here. and so we know from simple physics that pressure is forced over area and so that is 240 divided by 24. that tells you that the pressure being exerted on the back is ten times more than what the san diego people are training. they are off by a factor can. >> so the pressure being exerted by an knee is ten times greater is what you're saying? >> ten times greater than come is going to be affected by the bell here that is shown out of the gym, the bar that you're looking. >> do any of these studies involve an knee on the neck? >> nobody has been any studies involving the knee on the neck. i suspect it would have major trouble getting that through the ethics committee in any medical school. >> do any of the studies go on for nine minutes and 29 seconds? >> no. they are all very brief studies.
>> said doctor come have we now covered the four mechanisms that resulted in mr. floyd schaller breathing and reduction of the hypopharynx? >> yes, we have. >> -- shallow. >> were you or are you aware that mr. floyd had some pre-existing health conditions? >> yes, i am. >> and how are you aware that? >> i read them in the records from hennepin county and obviously also saw been mentioned in the autopsy. >> do you have an opinion to a reasonable degree of medical certainty as to whether a person who had none of this pre-existing health conditions, a healthy person, would have died under the same circumstances as mr. floyd? >> yes. a healthy person subjected to what mr. floyd was subjected to would have died as a result of what he was subjected to. >> are you also aware that mr. floyd was found to have type of tumor known as i picking glioma?
>> yes, i yam. >> and for the ladies and gentlemen of the jury , what is a pair glioma? >> it is a type of a tumor that is found in the parable indians come sometimes in the pelvis. >> is the finding of this significant to you as relates to mr. floyd and his death? >> no. because one of the key things about it is it is called a 10% tumor which means 10% of people secrete adrenal but that could be important but 90% of them don't secrete adrenaline. so you don't -- nine out of ten of the time you have no increase in the amount of adrenaline. >> so if somebody were to die from a tumor, from some effect would be a sudden death? >> yes. there's been six reported cases of people who have had those who
died suddenly but that's the total in the literature, six. those people who died have headaches. mr. floyd complained of a lot of pain and a lot of different regions in the street but he did not complain of headaches. >> so in terms of reported cases where people have died from paragangliomas over the entire world there are six reported cases? >> yes. >> on all those sudden death? >> yes. >> did mr. floyd died of sudden death? >> no. >> i want to talk you about the different subject that the jurors may have heard one of the officers say if you can speak you can breathe. >> yes. >> is that a true statement? >> it's the true statement but it gives you an enormous false sense of security. certainly at the moment that you are speaking you are breathing,
but it doesn't tell you that you're going to be breathing five seconds later. >> so let's talk about kind of why this is significant. so could you tell us about something that may seem obvious, that is, what is required for speaking? >> right. for speaking you only speak when you're exhaling. you have to blow air out and then you vibrate the vocal cords and that's all there is to speech. so it is air going across the vocal cords, fenofibrate and you speak. but to speak there are two things important. one is you cannot blow air out if you didn't take a breath in before hand. so you must have had an inspiration in to speak. second thing is you cannot speak if your brain is not alert.
so when you see somebody speaking, you know that have had an inspiration momentarily before they are speaking, and that there is oxygen going to the brain at the time that they are speaking. >> and by inspiration you mean they haven't taken a breath in? >> right. >> was a time of mr. floyd's speech during the restraint import your analysis? >> yes, it was. >> why so? >> because it tells us for the time that he speaking and he continues to speak for four minutes 51 seconds from the time thing is placed on his neck, it tells us that there could not have been complete compression, not the been total inclusion of the neck at that time for that time because he's continuing to speak for four minutes 51 seconds. >> is a brain sensitive to
oxygen deprivation? >> the brain do so sensitive to needing oxygen. >> what percentage is a body weight and how much oxygen doesn't does it consume? >> the brain is relatively small. it is only 2% of our bodyweight but it takes in 20% of all the oxygen that we take in. so the brain eats up oxygen at ten times the normal level. it needs a huge amount of oxygen because it's in the out millions of nerve signals every second. so it needs very high supply of oxygen. >> how long can the brain go without oxygen? >> that is well worked out. if you stop the flow of oxygen to the brain, you lose consciousness in eight seconds. >> if you might recall mr. floyd's last words, i can't
breathe, i those words significantly as a pulmonologist? >> yes. obviously they are important different ways. one is complaining to you of difficulty with reading but they are also telling me that at that time when he is saying please i can't breathe, we know at that point he has oxygen in his brain, but and again is the perfect example of how it gives you a huge false sense of security because very shortly after that we are going to see that he has a major loss of oxygen in the way that he moves his leg. and so it tells you how dangerous is a concept, if he can breathe or if he can speak he can breathe. yes, that is true on the surface but highly misleading. very dangerous matchup to have out there.
>> so if i'm hearing you correctly when he says i can't breathe that shows his brain is a? >> yes. >> i did meet them there wasn't? >> correct. >> and did you see or is anything in the video that you could show the jurors that they can see also that would point to the fact that his brain was a longer alert? >> yes. >> let me pull up exhibit 47 already in evidence. at 20:24. i'm going to play a a clip for you, dr. tobin, and then tell the jurors what they see afterwards. >> so this key finding that you
are seeing here, and that is when you see his leg going up come here to keep in mind he is prone so he is facing down. this is his leg coming up backwards. so that is what we call as clinicians, that is an extension of the of the leg and that is something we see when somebody suffers major brain, lack of oxygen. and it tells us at that point he is having what are sometimes called myotonic seizure, sometimes called hypoxic seizure. there are different terms that are used to really all about to say that you are seeing here fatal injury to the brain from a lack of oxygen. >> it sometimes also called anoxic seizure? >> it has all of the step of words. there's lot of different words that are used but they all come down to the same thing, that it is that at that point the brain is responding to be drastically
low level of oxygen at present. >> and does the fact when an anoxic seizure reflect damage to the brain? >> it indicates severe damage to the brain. >> and the reflex that we saw with the likes coming up, , is that an involuntary reaction? >> it is an involuntary reaction. there are a lot of different medical terms we apply but the bottom line is that you are seeing that the leg jumps out like that as a result of fatally low level of oxygen going to the brain. >> we talked about the brain injury. we also told us earlier about low levels of oxygen potentially causing pulseless electric activity. >> yes. >> is a also then evidence of low oxygen? >> right.
so, i mean, we have low level of oxygen that's going to show up in the brain and is also going to show up in the heart. and when it shows up in the heart it's going to cause the heart to beat abnormally. and the particular way that it happened in mr. floyd was you develop a particular arrhythmia called p.e.a., which is pulseless electrical activity where we are seeing their electricity in the heart but it is not resulting in any mechanical force. that is why it is asked that name. so it's the low level of oxygen is producing both. we don't see that dea and tell that is shown up on the ekg in the angeles. so it's much later that we see the evidence of it in terms of display. but here we are seeing huge
evidence in terms of the leg. the lake is crucial here because this is the time, the first time you are seeing there is major oxygen damage. >> so we reach the point where mr. floyd couldn't speak due to low oxygen. was it any correlation also to a narrowing of the airwaves that present his being able to speak? >> yes, as well. >> i want to show what is marked as exhibit 934, 936 and 933. and just tell us what are these images, in general? >> we are seeing again the same mri but as a different view of it that we looked at before. >> i offer exhibit 934, 936 and 933. >> any objection? >> no, your honor.
>> exhibit 934, 936 and 933 our received. >> is a doctor, tell us what we see here starting with the first -- >> this is the same mri you saw before, but what you are being, your attention is drawn to by the yellow arrow is the vocal cords. and the vocal cords is simply how you speak. so to speak you must inhale. you must take care into your lungs and then when you let the air out of your going to vibrate those little vocal cords and that's what makes the sound of speech. so here we see the size of the windpipe, the trachea, and this becomes important in terms of speech. because our knowledge about the influence of the size of the trachea, the windpipe for
speech, is from patients who have had an intubation to in place and it is to develop scarring after that pixel as a result of the scarring we know what is the point of how much scarring in your windpipe will prevent you from speaking. answer these are just the dimensions. so as you know what is the size of the normal trachea. it is between a quarter and a time, as you can see here in terms of the diameters. >> next slide. >> and here is when those coins have been shrunk to 15%. and even when the trachea has narrowed all the way down to 15% you are still able to speak. even when the whole 30 windpipe is just the size as i shown here i have shrunk the size of the coins you are still able to speak. so it tells you how dangerous it is to think, well, if you can
speak, he's doing okay. because at this point you will be able to speak, but again if there is a small increase in the amount of narrowing here, not only will you not be able to speak, you won't be able to breathe. you won't be able to live. so it is a very dangerous thing to think that because you able to speak you are doing okay. >> and so, doctor, you're not able to speak, briefed or live once the airway narrows to below 50%? >> correct. you go from 15% you will still be able to speak and then as it gets lower from that, initially you'll be struggling and then at some stage you just won't be able to do anything. >> if we could show exhibit 940. it's already admitted. >> so again this is exactly -- this is the same experiment i
showed you before. and it just so happens this is pure coincidence. it's at 85%. you look at the top curve and that's the same number that we showed you on the mri. this is pure coincidence but you can see here once you're up at 85% that the work of breathing is enormous at seven and a half fold increase. and then as as a narrowing wd get further and further, then the work will become unbearable. so again it just emphasizes at the point where you can't speak-
all right so i want to review a few things with you sir we won't take too long but you are ulgt matily approached by state of minnesota to assist them in the review of the medical issues in this case, correct? >> correct. >> and you have volunteered to do this work at no cost? >> corrects. >> you're not involved in criminal cases of this nature? >> correct. >> this is first team you've ever been involved in a criminal case correct? >> correct. >> it was that reason that you decided not to charge a fee, correct? >> correct. >> now, when you are in other cases what type of fee do you normally charge? >> i charge per hour. >> a what's your hourly rate? >> hourly rate is 500 and hour for material. >> okay. and you agreed to waive your hourly rate for this -- >> yes. >> you felt it was an important case right? >> yes. >> all right. wnow in preparation for your
you met withay, the state numerous times, correct? >> correct. >> you have had the opportunity to review all of the medical information that was obtain in the this case correct? >> correct. >> that would include mr. floyd's previous medical history correct? >> correct. >> the autopsy and the attending toxicology reports that were prepared in this a case? >> yes. >> as well as some investigative materials, police reports things of that. nature, correct? >> correct. >> and just correct me if i'm wrong but you're not a pathologist correct? >> correct i'm not a pathologist. >> your specialty is in care -- >> you have an interest in an impressive resumé relevant to applied physiology as well? >> correct. >> and you've been honored quite extensively for your work in that regard, right? >> correct. j you're the no a minneapolis police officer?
>> correct. >> fair to say that the training that is provided by the minneapolis police department in terms of medical care comes nowhere close to your level of expertise. >> correct. >> you understand that minneapolis police officers are not even emts. j correct. >> they have a basic life saving certificate dealing with gun shots chest shields and tourniquets. >>, you've also had the opportunity to review body camera footage. you have tested that you have watched these videos hundreds of times. >> correct. j and you've watched them all from all dincht angles correct? >> correct. >> you've had lung rei of slowing things down moving it into slow motion still framing various times right? >> correct. >> and so analysis comes after
hundreds if not thousands of hours time spent looking at this information. >> i don't know the total amount of time that i've spent but it is -- >> right so you ultimately based on review of all of that you prepared a report. j correct. >> you provided that to state of minnesota late january of this year. >> january 27th. >> and after that you've had numerous meetings with the prosecution team in this case? he>> by phone -- yeah. >> right. including january 30th of this year. don't know the dates but, i mean, that sounds correct. >> right. >> so if i were to tell you dates were january 30th -- march 3rd, march 9th, march 17th, march 21st, april 6 t, and april 7th you would not have any reason to dispute me? >> i have no reason to dispute. >> you understand that notes are made of those meetings and provided to the defense in this case correct? >> i understood that.
>> you've also been able to spend a substantial period of time preparing the exhibits that the jury was age able to see earlier today? >> correct. >> those were prepared by you or someone within your team. >> by me yeah. >> you provided those to the prosecution in advance of today's testimony? >> correct. > and you understand those we provided to me last night? >> i have no idea when -- yeah. all right. so you've had a lot of time to prepare both yourself as well as the prosecution team in connection with this case fair to say? >> correct. >> now you talked quite a bit about physics in your direct testimony. agreed? >> yes. >> and you would agree that physics or the application of physicalt forces is a constantly changing set of circumstances. >> repeat what you said. >> you would agree with me when you look at concepts of physics
these things are constantly changing. >> yeah all of the time constantlyly changing. >> in milliseconds nanosucceeds. right so n if i put this much weight or this much weight -- all of the formula and llvariations will change from second to second -- millisecond to millisecond nanosecond to nanosecond, agreed? >> i agree. >> similarly biology sort of works the same way, right? >> yes. >> my heart beats, my lungs breathe -- my brain is sending millions of signals to my body at all times. >> correct. >> geffen even faster than speed of light. >> correct. >> millions of signals every nanosecond right? >> yes. >> and i think in your report you even kind of discussed that when you're talking about these instances when you're talking about the physics or biology
what you're really talking about is a single kind of nanosecond but all of these processes are working in concert at all times right? >> the way we calculated this is mean t value but it has been -- into one instant. >> right. >> you've taken this case and you've literally boiled it down into a nanosecond. >> i wouldn't say that because it is, obviously, in my report as you see -- it is sequentially i begin when knee is placed on neck and then all of the time until what is happening in county er. >> so you talk your reports talk about the sequential nature of things but when we talk about biology ande physics of this case, these they thinks are working simultaneously contemporaneouslyne altogether, right? >> that's correct. >> in an incredibly rapid
fashion. >> yes. >> and you would agree with me that -- that as this distinct was occurring, there was nobody measuring the units of force that were placed on any particular position of any particular person at any particular moment right? >> there was nobody there making sure at the too many i agreed that. but there are all calculatable. >> unked. >> when you calculate them you have to boil it down into -- what you would call the mean or the average, right? >> correct. >> and so in whenever we look at the concept of an average, there are things that are happening momentses before, moments after. >> yes. >> forces will increase or decrease relative to the nanosecond of time correct? >> correct.
agreed.nd >> and ultimately when we talk about kind of the biology of things, pathologist tries to look at all of the intersection of all of the things that occur to a particular in a particular deaf investigation correct? >> they're not looking to do anything physiology. understood. >> but they're looking at how other -- factors may contradict to the death of an individual right? >> they're basically -- >> it is a yes or no sir so objection -- >> yes partly -- >> they're looking at things beyond a nanosecond -- agreed? >> no i mean i think -- in terms of the pathologist they're looking at a nanosecond they're looking at the nanosecond of death. >> right. but they're taking into consideration things simply that extend beyond physiology, right? >> either looking primarily at
pathology. whanch causes heart to stop what causes -- the lungs to cease to function et cetera right? >> they're making an inpresence based on pathological time point. >>al right. >> considering a multitude of tibiological factors that are involved in the death of a person. right? >>th the same as any physician s looking at a multitude of factors. >> so in terms again -- of your review, you would agree that the amount of time that you've spent looking at videos, analyzing these videos from different perspectives and angles is far greater than the length of this incident. >> yes. >>ar probably to the times of
thousands. >> i really dongt know. but it is substantially longer than the incident. >> right. now ultimately you conclude mr. floyd -- died what we would call a hypoxic death. j low level of oxygen. >> that there was a low level of oxygen that caused dalg to damae in the brain that resulted in -- activity. >> had you do you phrase it? >> low level of oaks that caused damage to brain. the brain didn't cause the -- low level of oxygen caused both. low level of oxygen caused the damage to the brain, the low level of oxygen separately caused the pulse -- >> so an example of how multiple processes are occurring simultaneously. >> it is just one process it is a low level of oxygen that is doing both. >> that's having an effects on
multiple -- heart and brain and the lungs, right? >> not really it is just two. brain and the heart. >> brain and the heart. all right. >> now you talked about about i think you called it the -- nuca ligament that's that space at the back of the neck that is very, very hard. >> it is a long bit but roughly your hand you stick palm of your hand back of your neck and you're right over the nuca ligament. >> a very, very hard surface and withstand great amount of pressure.er right? >> correct. and so when we talk about placement of the knee there would be periods of time where mr. chauvin knee based on that nuca ligament. >> yes --
you're had an opportunity to review the autopsy correct? >> i did. >> you understand that there was no bruising either atop the skean skin or under skean surfaces that were noted by dr. baker. >> yes, i'm aware. you are aware you talked a bit about hypoand nothing was noted. >> now i found it very interesting in your testimony in your report when you kind of are talking about this notion of if you can't speak, or if you can speak doesn't mean you can breathe sorry i have to state if you can speak you can breathe right? >> yeah. >> if you describe this as a very dangerous proposition. right? >> yes. >> you described this as causing false sense of security to people. right?t?
that's how -- >> correct. >> in fact in your report you actually write a paragraph about how physicians oftentimes have trouble with this right? >> yes. >> and so people who have similar to yourself attended medical school -- right -- sorry you have to say yes -- s >> terribly sorry. >> yes. >> so intelligent men and women gone ton medical school, and are engaged in the practice of medicine, sometimes have problems with this notion right? >> yes. >> they -- a patient comes in saying they're having trouble breathing oftentimes a physician will not believe them essentially. >> it's important -- to make sure we're talking about speech or difficulty in breathing. because they're different. >> well you were -- you were writing in your report that some doctors incorrectly consider patients to be
hysterical. >> may we approach -- >> your honor, the report is -- >> not proper. >> overruled. >> you wrote in your report that some doctors consider patients hysterical and symptom imagination in nature further aggravates patient distress. >> yes, i recall. >> you where this view represents physician failure to understand the fundamental pause ofst a clinical disorder. >> talking about a different thing that was hyperventilation syndrome. >> very different than the difficulty with speech. apple and oranges. >> but if physicians someone comes in hyperventilating they articulate to their physician i can't breathe. all right -- and it is hyperventilation syndrome right, and physicians oftentimessi as you indicate confuse this shall.
>> correct. >> they blame the patient. all right? >> i don't have blame the patient but they miss the diagnosis. >> and it's a -- kind of when we're talking about speaking and breathing simultaneously -- the different consideration if a minneapolis police lieutenant who trains police officers happen to have testified that that's a common statement in the course of treatment or in the course of training in minneapolis police officers. you might take exception with that statement. >>ou i didn't follow your question. ep>> i'm sorry -- >> hard to hear through that plexiglass. >> i'm losing my voice -- excuse me. if a minneapolis police officer tried to talk closer to the mic --
the minneapolis lieutenant who train a minneapolis police officer, testified that it is frequently said and trained to police officers that a person can talk means they can breathe. you would have a problem with that. >> yes. able to breathe at that moment in time. h but ten seconds later they may be dead. >> right. and because -- dealing with any person is a rapidly evolving situation that can change from second to second. >> yes. >> now, in terms of the calculations that you've made, you would agree that your calculations are generally theoretical correct? >> no they're not theoretical. they are based on direct measurements they are based on extensive research. >> but you're making certain assumptions in the application of that science are you not? >> very few assumptions. >> you're assuming weight of
mr. chauvin. >> i'm aware so, obviously, i'm aware there are two different weights that are given. >> and you're assuming the weight of the -- equipment that the officer wears. >> yes. >> and you've not actually ever physically measured the weight of the equipment of police officer correct? >> no. i mean, i took the measurements that are reported. >> and you're not actually weighing what mr. chauvin weighed on may 25th of 2020. >> no. >> and in your measurements you are -- you appear to be at least from my understanding which -- going to be limited, from my understanding is that your measurements assumed an equal weight distribution between right and left leg. >> yes. that's correct. >> so again as we know as things change and evolve and flow that
weight is pretty frequently redistricted right? >> that is correct. >> and again in terms of the eelv -- >> appendix lung volume. >> you're facing those calculations on the presumption that a person is a healthy individual right? >> for ealv it won't change. >> terms of the respiratory rate and some of the other factors that you put into your analysis, it is all premised upon a healthy ?rij >> based on of a particular height and sex, yes. >> who is healthy? >> correct.
>> and so -- you would agree from biology can change rapidly that the biological speck biological conditions of mr. shaven or mr. floyd come/o into play righ? >> correct. >> and those volumes or those figures that you've assessed in connection with this case -- they are conditioned upon him being a healthy individual? >> it varies in materials of the lungs, i mean, say for example compliance would vary but lung volume is robust. >> vary. >> so some other factors like you said -- it was first segment. >> no compliance vary from one person to the next person. but it is -- it varies different segments within lung they're not all
monolithic. >> you've talked about one thing in terms of and this is a little bit of a side in terms of your -- prone position and the pushing of the stomach into the lung. right? nt>> right. >> the size of a person's stomach has some bearing on that right? >> it does. j person like myself with a few extra inches if i'm prone it will push further or harder up into my lungs. >> yes. >> a person who is healthy, physical -- muscular, going to have less of an impact.r >> that's correct. >> all right. but again in terms of what we have learned about mr. floyd, from his autopsy and his medical records, is that we understand that mr. floyd had sol heart disease right? >> that's correct. >> in fact, i believe that he had in some of his artery somewhere between a 75 and 90% acollusion of his artery and that will affect blood flow in a
person right going to make the body work harder to get the blood through the body? >> no not really not good to do that. >> how does that affect a person's respiratory? >> the coronary artery it is affecting it, and if the coronary artery was contributing to shortness of breath you expect hees would be complaining of chest pain and you would expect that he would be demonstrating a rapid rate we don'tng see either. >> and we'll come back to the -- respiration -- i can't say it right. i'm taken by your accent. respiratory -- >> i can't compensate -- >> appreciate it. >> i'll say it like you his
respiratory rate. j we also understand that mr. floyd has a history of hypertension or high blood pressure. >> yes, that's correct. >> now, in terms of we also understand that mr. floyd had previously been diagnosed with covid-19, right? >> correct. >> he may not be symptomatic or having symptomatic on march 25th but fair to say that a lot is unknown about the effects of covid-19 on a person's lungs. long-term -- >> i mean, not as much as it would appear to be the case. i mean because, obviously, it is a viral and we have a huge amount of inflammation about the long-term effect -- >> and it can affect the elasticity of the lungs? >> not elasticity and having any effect it would be within the sensory receptors within the
trachea so nothing to do with the elasticity. j okay. now we also learned quite a bit about the toxicology as well. excuse me, on the covid-19 you testified that treatment of people with covid-19 includes leaving-1 them in the prone position correct? >> correct. >> those people treated for covid-19 in the prone position based ontr your calculations you have a 24% decrease in eelv. >> this is people with covid -- where they're during the team that they w have covid -- >> that is what you would expect that same decrease in the eelv? >> no it is going to be very different in somebody who has say -- pneumonia. what's going happen in the prone position will be very, variable from one fern to other as a result of the pneumonia. it is different than normal lung. >> so -- so inre that sense, every person
is different. >> for certain. >> and now -- you calculated his respiratory rate to be 22. right? >> right. >> you said that that was within the normal respiratory rate? >> yep. >> and you would not describe him as hyperventilating. >> word hyperventilation is off to more certainly not hyperventilation. no. m>> hyperventilation assists in removal of carbon dioxide from the body right? >> it is confusing it is nots that simple. >> simplest terms. >> simplest materials it does it gets rid of carbon dioxide. but it can be frequently misleading. now, in terms of the toxicology of mr. floyd, we did learn that there were some controlled substances in his system.
right? >> yes. >> we know that there was, for example, nicotine right? >> yep. >> mr. floyd was a smoker. ?>> correct. >> and smoking changes the lung function, agreed? >> in some people. >> now, we also learned more and i'm not suggesting people all people who smoke have lung problems. >>em less than 10% do more than 90% don't have any. >> so -- so you focused in your direct examination quite a bit in terms of fentanyl and effect on the respiration rate? >> yes. >> and you would agree generally that fentanyl is a respiratory depress. >> it can be.
>> it's used in operating rooming right? >> yes. for -- >> yes, and used used in managet of chronic pain.n. >> medically speaking those are only two reasons that fentanyl would be prescribed? >> yes. probably. >> but you understand that fentanyl has become far more prolific and street drugs right? >> yes i'm aware. >> and there's you would agree generally there's a significant difference between fentanyl that's manufactured according to united states, you know -- their whatever rules apply right? that pharmaceutical companies make it much differently than the street dealers do, right? >> i imagine so. >> right. so when you are -- when a person is in elicit street purchase fentanyl, it's every time they tick a fentanyl dose it is a different experience for that person.
>> right but if it is affecting the sensor it is going to act through the receptor in the fentanyl won't] have affect on respiration by some other mechanism. >> unked. understood but end result could include respiratory depression. >> right through the receptors. >> right. >> and we also learned there was methamphetamine in low dose in mr. floyd's system right? >> correct. >> and fentanyl and methamphetamine they can kind of counteract each other right? >> well, i mean they're up and downwards but in materials of the sensors there's not going to be. >> so the methamphetamine would not the methamphetamine is going to increase the heart rate right? >> that is a different thing than -- >> understood but methamphetamine will increase a person's heart rate that's one of the side effects -- >> yes. >> and there are a few
lawfully -- through a few conditions where a physician can lawfully prescribe methamphetamine. right? >> yes. >> but it is exceedingly rare ntthat it is actually done. >> i can't say but, i mean, it is definitely a prescribable agent used to be used in commonly for suppress. >> adhd is that right? >> yes. >> yeah, so -- we also know that adrenaline will increase the heart rate right? >> yes. >> and adrenaline can be put into the body and multiple ways, right? >> let me -- there are many things that can cause a surge in adrenaline. >> yes. >> one of those things would be getting into a fight with somebody.
>> yes. >> or being afraid. >> difficult knowing in terms of being afraid but getting into a fight. >> pairyou found 10% tumor but 10% of the tumor cases that can cause adrenaline surge. >> yes. i mean the 9th.to 12. >> now, in materials of the use of fentanyl in the hospital setting surgical setting, have you become familiar with a what's called wooden chest syndrome? >> yes. i have. >> can you explain for the jury what wooden chest syndrome is -- >> with some patients you get increase in chest -- so lungs become less elastic? >> not quite lungs but chest wall. >>es so that would -- prevent a chest wall or chest
wall also decrease the performance of the lung. >> it would impede ability of the listenings to expand. lungs. >> now in your report you wrote that you would expect peak respiratoryxp depression to occr within five minutes of ingestion. >> right. >> and have you come to learn that tablets were found or control substances were found in backseat of squad 320? >> i've heard reports that effect i don't know what status of it is. >> so you were not you've not been provided with any additional information since the time you've prepared your report? >> i no -- i'm sure that's wrong. but i've been -- provided with a lot of information i don't necessarily recall keeping it all --
front of my brain. >> well yesterday we heard testimony from state crime lab that there were in the backseat of the squad car two partially consumed pills thrown in the back squad 320. >> objection your honor -- characterize -->> >> characterize of? >> overruled foundational to your -- >> it is. you understand that? >> no. >> i kind of but not fully. >> okay. >>am yesterday -- chemist from the state crime lab testified in this case. [inaudible conversations] >> ruling it is disdained. >> sorry i can't hear you. > side bar.
fentanyl and methamphetamine were found partially ingested in the backseat of the squad, of the squad car, and that those pills had been -- had come had the dna of the deceased individual on them meaning that they took them -- >> uh-huh. >> and those pills would have been in his mouth at about 2:18 or 20:18 right is it fair to say that you would expect a peak fentanyl respiratory depression within about five minutes? >>ss right. obviously, it would depend on how muchut of it was ingested, i mean, it just finding pills won't tell you anything about whether any of it was ingested or some of it or losing it or anything. but if therer was any amount it would be in five minutes.
>> if it happened when the individual was in back of that car you would ppght that peak respiratory depression around 20:13 right? >> 20:23 i'm sorry -- >> 20:18 to 20:23. >> i'm sorry you're trying to really confuse me. >> it has been a long week now -- so 20:18 is ingestion and peak respiratory by 20: 23 right? >> so that peak meaning that it can continue afterwards right? >> right. >> all right. you also described in your direct testimony what you have interpreted to be an seeture at
20:24:21. >> and that was in what you saw and what the jury was played was reflengted in from officer lane's body camera. >> correct? >> correct. >> it was the kick of the legs. >> right. after that point you can see officer lane hold the leg down right? >> yes. >> you can see it kick up again right? >> yep. tendency to go fast. >> okay. >> that's what you recognized based on your 46 years of being a pull monoologist. ol>> additional information from the hand but leg was the key. >> right. >> and would be reasonable for a police officer to interpret that sameea behavior as resistance. >> objection your honor foundation of the witness to talk about --
[inaudible conversations] now -- you testified that the last breath ofti mr. floyd was at 20:25-16 right? >> correct. >> prior to that point to all people who were there and monitoring him, he would have appeared to have been breathing right? >> it is just hard for me to hear. >> prior to that point -- would be reasonable that he would appear to be breathing, right? >> right. >> in fact you showed us a segment where you were able to count his respiratory rate. and then you said that at 20:35 and 06 seconds when first air punched pumped back into him. >> correct. >> you understand paramedics
rifed atnd 20:27 and 45 seconds and time between paramedics arrive and mr. floyd got his first air was roughly -- eight minutes almost nine minutes. >> yes. >> yep. according too timeline drive to the hospital is about five minutes. i'm sorry -- i didn't catch that. >> drive to the hospital is about five minutes? >> i wasn't aware but i have no reason to dispute it. >> and so between 20:27 when emt first arrived, and the time they got him to have an air in his lungs, that was a crucial nine minutes. >> yes. >> your honor, i have nothing
further. >> mr. blackwell. [silence] dr. tobin just a few questions just -- clarification sake, you were just asked a lot of questions about science meld, changing constantly changing, evolving, by nanosecond and millisecond all of that. i want to go to the period of time when mr. chauvin was on the back and neck of mr. floyd. >> yes. >> did you see him get off of the backd, of mr. floyd by the nanosecond and 29 seconds that you saw him on him? >> no i did not. >> if you look at the five minutes and three seconds that you focused on, where if you
consider all oft the nanosecond and milliseconds in the five minutes and three seconds where wasut mr. chauvin the vast majority of that time? >> he was on mr. floyd's neck and on his back and arm. >> right not constantly changing? >> no. >> now you asked questions about what injuries were noted on autopsy. >> q yes. >> and i think reference was made there was no injury to hyper-- does that make a difference? >> i wouldn't expect there to be anything found there. >> why not? >> why not dr. tobin? >> because affects on that are not something that is going to remain at the time of the -- the type of changes that we see say in somebody with sleep apnea that's not sthng you see the following morning when you look at somebody. n it is just not there. there was a reference made to bruising on neck during autopsy.
>> yes. >> does that make any difference whatsoever? >> no, obviously, whenever i go to church i sit on a hard bench. i don't get bruising of my buttocks when i leave so i wouldn't expect anything. in terms of that -- so if you have somebody this was a stat static force not as if somebody is jamming against so you wouldn't expect anything way of bruising. >> scientifically do you know of any correlation between the presence or absence of bruising on autopsy and the forces necessary to restrict breathing? >> no. they're totally different because it's in terms of stat tick forces and dynamic. >> what about low oxygen if somebody has suffers or dies from lowow oxygen -- >> yes. >> does that show up on autopsy? >> no it does not. >> does that mean anything to you whatsoever? >> it has no meaning. >> why not? >> because low oxygen is a
functional thing just like arrhythmia is function of thing it doesn't leave a finger precinct on the autopsy. it is just there. it is something that happened. it's -- butom it won't leave any fingerprint afterwards you don't see it. >> l but does it mean that persn didn't die of oxygen -- >> no. it don't so if you suffocate them with a pillow and it is very clear to you after you suffocated personsu and he's ded from the pillow you're not going to see the effects of the low oxygen. now, you were asked quite a few questions about mr. floyd's preexisting health condition. >> correct. >> remember he cited number of those. >> yes. >> do any of those conditions have anything to do with the cause ofmb mr. floyd's death in your professional opinion whatsoever?yd >> none whatsoever. >> and again, what was the cause such as those conditions don't matter? >> the cause of death is a low level of oxygen. that caused the brain damage and
caused the heart to stop. >> you were also asked questions about substances in mr. floyd's system, i think you were asked questions about nicotine remember that? >> yes. >> he didn't die of nicotine did he? >> no. >> you were asked questions aboutt fentanyl and meth. >> yes. >> any evidence he died from meth? >> aen no, none. >> you asked questions about whether he had ingested any fentanyl within five minutes of his time of death. >> yes. >> now i think you explained to us that if somebody is suffering from a fentanyl overdose, you would see a depression in respiratory system. >> yes. >> and depression means some reduction in the rate of ability to breathe.. >> correct. >> did you see any depression in mr. floyd's ability to brought whatsoever before hee went unconscience? >> absolutely not he was normal respiratory rate. >> any evidence that any
fentanyl depressed his breathing in any way whatsoever? >> no. that's further from the carbon dioxide -- >> thank you doctor tobin no further questions. >> anything further in? >> two very quick questions in terms of the carbon dioxide level, do you testify that television at a 96 or -- >> yeah. >> i'm sorry. i can't catch. >> you testified that the carbon dioxide96 was at a 96? >> i think it was 89. >> it was also measured at 102 do you -- >> that was beat -- the one you need to look. >> and in terms of the ingestion of or just generally speaking fentanyl can also cause death as a result of low oxygen to the brain, right? >> but it would to be low to whisper -- >> question is fentanyl can also
cause a death as a result of low oxygen. >> your answer is yes but it won't be -- >> fair enough, thanks. >> please this way -- mr. nelson brought up again fentanyl is cause of death. doctor -- you're familiar with the way people die from fentanyl. >> yes. very.re >> do they or do they not go into a coma before they die from a fentanyl overdose? >> yes, they will. >> mr. floyd ever in a coma? >> no. >> thank you dr. doaben. >> okay. anything else? >> thank you. >> doctor thank you so much. you're excused. thank you. let's take a five minute break so we can all get our voices back.
[silence] coming up live today, the american bar association looks at the legal challenges of unaccompany migrant children at the u.s. southern border. at 11 a.m. eastern on c-span. then at 1 p.m. a discussion about the pandemic and vaccine hesitancy from center tray strategic international studies. and on c-span2 at about 10 a.m. eastern, the trial continues for former minneapolis police officer derek chauvin. who is charged in death of george floyd. ♪ ♪ c-span2 is your unfiltered view of government created by america's cable television companies. today we're brought to you by these television companies. who provide c-span2 to viewers as a public service. ♪ ♪ >> back now to day nine of the
trial for former minneapolis police officer derek chauvin. this portion includes witness testimony from a forensic toxicologist. >> next witness please. >> thanks your honor. thanks. [silence] raise your right hand please swear or affirm that testimony you're d about to give will be e truth and nothing but the truth? >> i do. >> please be seated. if you wouldn't mind remoing your mask for testimony if you feel comfortable doing so. an let's begin by having you state your full name spelling
eachch of your names. >> my name is daniel d-a-n-i-e-l-i-s-e-n-c-h-m-i-d-t. >> where do youft work? >> labs in pennsylvania. >> yeah. >> how long have you been with in a meth lab? >> since 2011. >> what do you do in a meth lab. >> forensic toxicologist at mns. >> did you have any other lab experience before joining nms. >> prior to joining from 1994 to 2011, i was a chief toxicologist for the wayne county michigan medical examiners office, and before that, i was a south gate medical lab -- so i did a director of the toxicology. and prior to that it from 1982 toto 1991, i was maryland labs
during that period working at some time during 6 to 84 to 86 at the medical office in baltimore as well. >> so rewinding built as well to your educational background could you just describe for the jury what your educational background is. >> sure. i have a bachelors degree in biology from a university in garden city, new york. and that was obtained in 1982. then of a master's degree in forensic pathology with actually pathology with a cons treens in forensic toxicology, and that's from university maryland baltimore in 19 -- 1986, and then my ph.d. was from university of yanked in forensic intoxicology in 1991. >> do you have any specialize certifications reallied to your work? >> i'm board certified of the fellow from american board of
forensic toxicology. >> what are requirements for that? >> the requirements for that -- they've p changed over years but for fellow requirement you can apply to the board after three years after you have your ph.d. they examine your credential to see you're active in field of forensic toxicology. if you have the right references in your active in the field they will allow you to sit for an examination and then if you pass the examination -- the board votes on your final certification. after that you have to do continued education each year and obtain a minimum number of continue education credits, and then every five years you have to reapply to board for reaccreditation. >> have youou gone through requirements satisfied them successfully? >> yes. >> are you up to those continuing education requirements as well? >> i am. >> i'm going to get back to sort of your role as a forensic toxicologist could you describe
sort of your day-to-day job duties as a forensic toxicologist at ms labs. >>r my primary job is to do case review and what that means is when toxicology tests are performed at msn labs ones that require many different kinds of tests to be done, they wind up being reviewed by a toxicologist or certifying scientist to look at them in context of all of the testing that was done. so individual tests are reviewed by analystst in a laboratory and they're second dares reviewed as well but final review comes to either a toxicologist or srt if iing scientist that looks at everything in context of the entire case. >> and then in that capacity is it part of your job duty to sign off on all of that testing? >> yes, it is. >> approximately how many cases have you reviewed in that capacity as a forensic toxicologist? >> i review about 7 to 8,000 cases per year. h
in terms of work that comes into msn lab is there agencies that submit for testing? >> yes we get samples from medical examiners and coroners, we get samples from police agencies, for dui cases and we also get a lot of clinical samples from hospitals and referral laboratories. >> so in that capacity, does mns receive both death related samples as well as samples from living patients? >> we, we do. >> approximately how many tests or samples does mns receive for testing each day? >> we receive about 12 to 1300 each day? >> it would mean requests for testing. it could be multiple samples on the -- >> thousands of tests year. >> thousands of tests day.
>> tens of thousands of at the s year by that -- all right. is mns a license and accredited lab? >> it is. >> does that include national accreditations as well? >> national and state. >> i'll turn to your work many this particular case. did mns lab receive samples for testing from the county medical examiner office related it to george floitd? >> we did. >> were there a number of different samples that were received? >> correct. >> what were the samples that were ultimately tested by msn lab? >> we tested samplets that were requested by the medical examiner to be tested. sore we tested samples that were label the as hospital blood, and we also tested urine that was collected at the autopsy. >> in terms of the testing that was performed at msn lab were
those tests pursuant at the lab. >> yes. >> they were followed for all of those in the lab. >> getting to results from that testing, what were the notable findings from that testing? >> most notable findings in the hospital blood was present of fentanyl at 11 nanograms per milliliter and then fentanyl break down product of fentanyl more had a concentration of 5.6 nanogramsf per mill leader and n addition methamphetamine at 19 nanograms per milliliter. >> talk about each of the substances one by one and you indicated these were the results from the hospital blood in this case is that right? >> that's correct. >> so let's start with -- methamphetamine, what is methamphetamine? >> so methamphetamine is a central nervous system stimulant. it can actually be prescribed it
rarely is but it can be under and it is used for attention deficit hyperactivity disorder and also obesity. it is also experimental use for treatment of narcolepsy and between 2016, 2018 there were about 10,000 prescription used for each year. j can methamphetamine be both a street level recreational drug and also prescription drug? >> it can. >> with respect to these result 19 nanograms that you found of methamphetamine,he what significant of any is there to that amount? >> that actually is approximately the amount that you would find in a blood of somebody that was given a single dose of methamphetamine prescribed drug. >> when you say you described the prescription drug form in which methamphetamine can be available, the result can be
king the with the prescription dose of that. is that right? >> yes. it could be. >> would that be considered a low i level of methamphetamine? >> yes. very low. >> and you also talked about the fentanyl results of 11 nanograms first what is fentanyl. >> so fentanyl is a both opioid and used similar to morphine. but it is much more potent than morphine it can be used to treat pain and also be adjunct use in surgery for -- anesthesia. >> you talk about opioid maybe you can describe what opioid is. >> it's opioids are actually include both natural drugs that act ongs a receptor where opiois act opiates are a natural
product that are found in a plant such as morphine and codeine so opioids but not all opioids are opiates. >> what are some examples of opioids? >> so fentanyl would be an example of an opioid? >> oxycodone with an opioid? >> yes, it would. j and then you talked about similarities between opioids and opiates is that right? >> yes. >> you mentioned more morphine as on opiate is that heroin? >> so harn is a -- heroin is made from morphine but when heroin breaks down it breaks down into a morphine and then eventually to morphine. >> heroin break down into morphine is that right? >> do opioids and opiates have similar effects? >> yes. >> getting become to fentanyl level in this case you mention
11 can fentanyl levels vary widely on vimg. >> yes. >> why would that be? >> because of tolerance. >> and -- could you explain how drug tolerance might affect the impact a particular drug like an opioid or fentanyl might have on them. >> so if a person becomes tolerant to a drug you need to have more and more of the drugs toru get the desired effect. so with cron chronic use to get the same feeling that you would at a given concentration of fentanyl you need more to get that effect. >> so if someone is regularly using opioid or opiates would that individual develop tolerance to fentanyl? >> yes. >> all right. now you also talked about norf fentanyl what is that? >> so when the body gradually eliminates fentanyl is breaks it down from fentanyl to norf that
occurs over time, and it is one of the ways that a body e elements fentanyl. >> you indicated that amount of norf found in the hospital blood was 5.6 nanograms per milliliter. >> yes. >> what is significant about that amount? >> well, it shows that some was metabolized and preexisting with additional fentanyl given on top that have but basically shows that when we see -- when we see very recent deaths with fentanyl we frequently see fentanyl with no norf whatsoever because after intoxication body doesn't have time to break it down. ... see in overdose typical you y not see it. >> correct.
>> in addition to those findings from the hospital lab, where there in the findings as included in your report. >> there was an incident the findings i believe there was coding which had been smoking, there was there was caffeine.e there was evidence of marijuana use with the presence of cannabinoids. i would look at the report -- >> with that refresh your recollection? >> yes. >> if we could put on the screed just for the witnesses recollection exhibit 624, please. and then if we could zoom in on the positive findings portion. all right. referring to the report now, could you describe the other findings with respect to this case? >> the additional finding was compound called -- the precursor
to fit no manufacturing but it also a metabolite to fit no. it's not chronologically, is probably mostly inactive but it was measured as part some additional testing that was requested by the hennepin county medical examiner. and then that the urine findings we had presumptive policy findings not confirmed for cannabinoids amphetamines and fit no. those are not conferred because they were present in the blood so that follow that. we also had findings for opiates in the urine and were asked to confirm those, and we found the concentration of morphine in the urine of 86 milligrams per milliliter. >> you were saying you found morphine in the urine, 86 ng/ml come is milliliter, is that right? >> correct. >> was at morphine found in the blood? >> no, it was not. morphine in the urine be indicative of a
prior use in advance of the time of death. >> yes, i can. you can see morphine in urine for several days. depending on the dose and prior use pattern. >> and again, said because it shows up in urine longer than in the blood prayed. >> yes. >> so you tested both the hospital blood in the urine in kenya describe the findings in the urine with morphine and you're also discussing it the key findings in the hospital blood but they effect to the other findings in your part, can you summarize with the work and if they were significant at all. >> you mentioned campaign, which is present in any of us. encoding which is present in the metabolite of nicotine, from smoking. and then kevin abba noise, thc, 2.9 nanograms per later in his
breakdown products of hydroxy and thc in 1.2. and in the inactive carboxy thc 42. >> and when it comes to the thc findings, relating to canada but noise, when impact is that have pretty. >> are doing turbid that but given the nature of the samples, and also what happens with them because they go into the back so they can be released slowly over time. anything like cpr could potentially release thc from the fatso and doesn't really mean a whole lot other than it was used at some point in time pretty. >> so i can made in the system and be detected for some time. >> yes. >> so we can take the down thank you. as part of your testing process at the lab, with their also some
metabolite or other substances that were detected as part of the testing buffalo the lab reporting limits pretty. >> we did find substances that were below the threshold of two report. and that is why they're not on the report. they are part of the data package that was requested and one can see those there pretty. >> do you keep those litigation packages with that date as part of your standard operating procedures of the court business at ms as bat labs pretty. >> all of the data in the litigation packages actually pulled from that data on request but yes. >> so as part of the testing of the lab testing of the samples in this case, i would like to ask about the testing process for methamphetamine and whether there were findings of amphetamines unit. >> so when we test positive for methamphetamines, at the - and
anything that is positive about 81300 certain professional by that procedure is been confirmed by an alternate procedure. in this case methamphetamine is positive in the screen and then we ran the confirmation test for amphetamines. in particular the test consisted of ten compounds. but were only interested in the larger compounds that were actually confirming in this case. so in this case we did check for kevin for the main and because of catalyzing, there was evidence of impediments but below the reporting limit so it was parted. >> and you recorded that. and does that mean that the body breaks down methamphetamine into and can mean overtime pretty. >> yes. >> in addition to confirming the presence of amphetamines, was there also an indication an on initial testing for morphine. >> there was an indication on
the time-of-flight screen but because it was below the reporting limits, it was not confirmed nearly hundred barely an education pretty. >> that just means it didn't go through that second process. >> yes. >> typically describe for opioid therapy for people that are going through opioid treatment. >> and other components of it, also in the lockdown pretty and it's an essentially a generic narcan. >> yes. >> getting back to the blood communicated that was hospital blood. correct. >> what is significant for that pretty. >> will hospital blood if it is more rep. of what is actually circulating in the body prior to
the time of death. after death, there are changes that occur was hard concentration that particularly an essential blood collected from heart. that's a post more than distribution with the drugs go from areas of higher concentration to lesser concentrations. that wasn't an issue, such as blood but it can still occur. ideally you would try to get a sample is close to the time of death as possible. >> were some samples taken after death. can there be some postmortem redistribution. >> i think that is possible parted it is a lot we don't know is certainly is possible and intends to increase concentrations rated. >> when you say increased conservation is having the level or higher than it actually was at the time of death.
>> correct. >> what about how wallace's pretty. >> that his breakdown of the red blood cell. >> and did that have any impact on the testing in this case. >> no, that would have impact on certain clinical chemistry tests like potassium. the store the red blood cells when you analyze the blood sample for drugs, penalizing the whole sample. it would have no effect. >> so you mentioned that the lab received samples the day and thousands of samples a year, you compile data from the year 2020 with respect to conventional cases methamphetamine cases with us help you conceptualize the results in this case. >> sure. >> for demonstrative purposes,
>> thank you, your honor. doctor, i'm going to have you describe what is shown on the screen. >> as of right now, we are looking at what happened when the levels metabolize over time. so gradually, the amount of fentanyl start to increase. [inaudible]. >> and that is what would happen is it metabolizes fentanyl. >> correct. >> can you describe what is shown here pretty. >> so this is data from the labs from the year 2000. we look at the fentanyl concentrations in postmortem cases specifically in those and only those, that were collected in non- peripheral blood for the reasons that i mentioned before, cardiac blood can have a significant postmortem distribution so we wanted to have her look at samples at a
minimal amount of that. >> this was in the year 2000. with this from 2020 pretty. >> that was my mistake, it is 2020. this was the year 2020 printed we had 19100 - cases that we looked at and in studies postmortem cases, the mean concentration or average is 16.d in the median concentration was ten, median being about 50 percent above and 50 percent below. >> and with respect to the peripheral blood you've indicated that you chose the samples that would have minimal post morning distributions. why is that. >> because the sample that you have from the hospital blood he is probably going to have less issues of post morning redistribution had invented postmortem blood.
>> and in these cases that are represented postmortem cases, these cases that you would be getting from offices of the coroner's office pretty. >> correct. >> where they are deceased or dead. >> correct. and also for the concentrations, those were 6.01, the means the median data 2.2 nanograms per meal the ability to predict. >> just a clarify. with respect to these cases, the average levels of fentanyl was 15.8 nanograms the average level for 6.01 handicraft per milliliter. >> correct. >> what is shown here printed. >> so this slide shows postmortem cases and again for the year 2020. so out of those 90185 cases we had 15455 that included fictional and more fentanyl but there was 3,071,204 cases with
no more fentanyl. there were exceptions for that for reasons of testing purposes. but those ones that were only fentanyl. a. >> so the site indicates there was a significant number of this thousand 71204 cases where there was fentanyl but no more fentanyl et al. >> next slide please predict. >> so this is switching gears, we are looking at the duis driving under the influence hotel concentrations that we founded in 2020. so these are blood samples there sent to the labs needed for the people that were suspected of driving under the influence of drugs. and also potential of the reasons the way they were driving. in this case we tested 2345 cases that were individuals that
were alive. and other drugs may be present but this was specifically looking at fentanyl winning concentration of 9.5 nanograms per milliliter 5.3 and the norfentanayl of 5.42 in the medium of 2.2 pretty. >> just to clarify, please 2345 cases, those individuals were alive is that right pretty. >> correct. >> and the average fentanyl levels were 5.9. >> yes. >> and the average norfentanayl is 5.4. >> yes pretty. >> next slide please. >> so this is just a break it down of the fentanyl concentrations we found it in the drivers were alive read so almost the majority of them were under 5 nanograms of fentanyl.
we had another 26.3 percent between 5.1 and 10 nanograms per milliliter in the next set of data was led to her sitting cases which were between 11 and 15 nanograms. so that would be the same. that mr. floyd's level of 11 nanograms. that we had quite a few cases that were even greater than that. we had about a hundred and nine between 16 and 20. anyone between 21 and 26 and then we actually have 53 cases in subjects where it was greater than 50 nanograms per milliliter. >> comparing mr. floyd's level to the driving population, the individuals were alive, his level was within a quarter of the pie the dui cases the lab received pretty. >> will be right in their grade
yes. >> and you indicated that those levels for drivers were found in 53 cases higher than 60 nanograms per milliliter. as of those individuals were alive advantage when driving at the time pretty. >> yes. >> so this is basically concentration and samples blood samples that were submitted by mr. tran five and we found fentanyl and 11 nanograms milliliter. >> next slide please. >> so this slide shows what the ratio of the parent drug is an 11 grams divided by 5.6 for the
>> subdues the show in which the way that you would calculate it. next slide please. let's start on this slide pretty. >> so the slide shows the ratios of fentanyl levels between nine and 13 nanograms per milliliter so that range was chosen because mr. floyd concentration was 11 nanograms per liter and when we do driving under the influence work, we actually assign an uncertainty of measurement to that result. so if the driver had an 11 met nanograms present we would report that is 11 nanograms plus or minus 2 nanograms per milliliter. so i did this to see what kind of ratios do we see between postmortem in dui cases in the fentanyl levels is between nine and 13, the kind of ratios that
we see. and we can see in the postmortem cases, mean ratio of fentanyl and norfentanyl was 9.05 with a median of .8. versus the dui population remained was 3.2 and 2.24. >> just to clarify, in the bar that shows the postmortem cases, without 3088 cases that you look at between the range of nine - 13 milliliters. >> yes. between nine and 13 pretty. >> the ratio was .05 on average is that right pretty. >> correct. >> with respect to the dui cases, cases between the range of nine and 13 are milliliter, the right. >> correct. >> so the average ratio is 3.20 rated. >> yes. >> how does mr. floyd's ratio
compared to that data set rated. >> so george floyd's ratio is roughly just a little bit below the median ratio in dui so postmortem cases we know that are fentanyl concentrations, would be much higher than the norfentanyl because of the frequent, these are deaths due to fentanyl. other drugs may be present they can be other reasons for that debt, doesn't say this is only intoxication but just looking at it as a whole, large amount of data is what we observed. we know with the dui population, they are alive but of the drugs may be present as well. so it's really just sort of looking at how things look differently in the postmortem population predict. >> and this site also shows that mr. george floyd's a ratio with the average and even below the median for that found in the dui cases. >> yes. >> next slide please. >> so this slide is actually sort of a summary of a previous
slide but it basically shows the relationship between fentanyl and norfentanyl and between postmortem, the dui cases and mr. george floyd freighted. >> and it shows how the norfentanyl levels increases over time over the fentanyl levels. >> and metabolizes. >> next slide please. you also look at data with respect to methamphetamines for 2020 and the meth lab. and what is shown in the slide as of right now predict. >> this slide shows concentration of methamphetamines found in mr. george floyd's hospital sample, it was 19 grams per milliliter. and as we talked about earlier, and had me was below the reporting limits. so it was not reported. ... ...
we had 3271 cases that had methamphetamine driving under the influence. 2009, 75 included amphetamine 296 were methamphetamine. >> we are talking about the dui population, individuals 3271, individuals who are alive. >> next slide. >> this is a further breakdown of what we see in methamphetamine cases. the concentration and all dui cases was 378 of
methamphetamine. median was 240 nanograms a milliliter and in the five to 25 range was five, being the lowest, we had 192 between five to 20 milligrams a year which is in the range of mr. ford's methamphetamine. >> mr. place level was 19 nanograms a millimeter? >> yes, it says on the bottom and again 94% dui cases mental contrition. >> mr. .9%. >> correct. >> next slide. what is shown? >> this is a further breakdown of what methamphetamine concentrations we've observed in drivers in the past 2020 and again other drugs that may be
present in this case we had 196 cases between five and 20, 360350. 571 between 101 to 200. 578 between 501 and 1000 and an additional 215 cases methamphetamine was great. >> again, you had to 15 cases where the number was greater than 1000. >> correct. >> the biggest piece, 30.9% cases were between 201 and 500 grams a milliliter. >> yes. >> mr. flights level was exceptionally low? >> in relationship to the dui, yes. >> nothing further, your honor.
[background noises] [inaudible] are right, it's a little unusual for you to testify in a death case, is it not? >> not terribly, i do work with medical examiners specifically are the ones to testify cause of death, usually i'm involved in a death case, it's usually growth resulting in death. >> so you work in a laboratory that works with medical
examiners from your own country? >> correct. >> you perform these services in a variety of different contexts? do not just. >> so you testify some are clinical in nature, some are law enforcement in nature, some are death related? >> correct. >> at the time you became involved in this case, you are obviously aware of the significance. >> yes. >> your laboratory goes through an accreditation process? >> we do. >> part of the accreditation process is to establish standards and reporting? >> yes. >> so the reason i laboratory will have the threshold is to be consistent in how toxicology is reported to various ways?
>> correct. >> one of those accreditation standards is to have and set this of a particular chemical component below the threshold, he would suggest it on the report? you are saying not there are instances where medical examiner if something was present at the lower threshold and depending on what the situation is, it could be reported as such, not common practice. in this case from. >> it is not common practice to report things that are below are chemicals below the threshold because it's contrary to the accreditation standards, agree? >> it does depend on the situation but by and large, if there is a reason we have cutoffs, we go below those, it's
basically not something we would typically do. >> so an analyst comes in hypothetically and when you see certain markers have an indication thing, that would be because of the accreditation. >> i'm not quite sure i understand hypothetically comes in and a question is presented about the presence of a particular substance, the substance was below the threshold -- >> your honor. [inaudible] >> it's a hypothetical. the analyst acknowledge the
possibility that would hypothetically be because of the threshold rules rex. >> i really can't speak about the crime lab because i don't work in the area so to me limited to toxicology and analysis blood or urine. >> so in other words, the reason we have these thresholds is the we set the rules, right reasons the thresholds were established has to do with validation will. thresholds are not set because of any it's what you have to use as a threshold, laboratory establishes those in right in
accordance with validation. >> sop being standard operating procedures so if the laboratory states this standard and says here is the standard and then does something or reports something against that standard, that would be a violation standard operating practice? >> if it were reported without affirmation, yes. >> a few follow-up questions to your testimony, he was met with or spoken with members of the prosecution team several times? >> yes. >> including february 26, march 5, march 12, april 5 and april 6? >> that sounds right, i don't know exact date. >> understood. >> he wouldn't disagree if i
told you those dates? >> correct. >> summaries of your conversations. >> correct. >> onto make sure i understand the difference between fentanyl and north. you would agree fentanyl is the active ingredient when you report the fentanyl concentration, the active ingredient? when a person and just essentially any substance, controlled substance, doesn't have to be an illegal drug, the body metabolizes that? >> correct. >> the body eliminates that? >> yes. >> through natural processes of the body. >> yes. >> the elimination of the substance results in a metabolite? >> yes. >> fentanyl, being the active ingredient, nor federal is the top? >> correct. >> in this particular case you
discovered fentanyl concentration of 11 nanograms a milliliter? >> yes. >> a level of 5.6. >> yes. >> you testified on direct examination that that could be one of two scenarios occurring? >> yes. >> one scenario is that a person took a certain amount of a -- fentanyl and enough time has passed to eliminate that, correct? will break it down into a metabolite. >> that is one. >> the other scenario is someone took some, the initial dose began to break down and the person took more so the active ingredient there but had not yet broken down, right? >> correct. >> so it either -- you described i think as an acute ingestion?
or non- acute ingestion when you have fentanyl, fentanyl will break down more fentanyl but still take more fentanyl so you can take it while the first fentanyl was breaking down? >> correct. >> put into context of people who may consume alcohol, i have a beer, my alcohol concentration will rise to a certain level, right? based on the alcohol concentration, agreed? >> yes. >> my body immediately decrease eliminate alcohol. >> correct. >> i have a second fear, i add more alcohol was in my blood alcohol concentration to rise, correct? >> yes. >> that's similar with all substances including fentanyl? >> in general, yes.
alcohol at a fixed rate over time, there's only so much you can eliminate, some drugs are a little. >> some may be faster, some may be longer. when you describe the results in this particular case, you're talking about -- i'll straighten that out, sorry. based on a strict interpretation of test results, there's no way to determine at what time in a particular amount of fentanyl was adjusted, agreed? >> i would agree. >> fentanyl, being a toxicologist is a lawfully manufactured controlled substance in the united states. >> it can be described backpack, lollipop, they can put it in lollipops. >> the fentanyl contain in a
patch or lollipop, by an anesthesiologist is in a controlled manner? >> yes. >> when we are talking about illicit drugs that include fentanyl, you have no way of knowing what the particular fentanyl concentration is filled to fill? >> yes. >> every single pill you take becomes a unique experience for the person, right? >> that's true. >> regardless whether you have tolerance or non- tolerance, any single incident can cause adverse reaction? >> for sure, if somebody had a pill ten times fentanyl that another, then yes. >> and you have no idea? because they are not manufactured in a controlled environment. >> yes, sir.
>> in terms of to understand there were some pills on the floor of the squad car? >> that is my understanding, yes. >> the pills were tested containing the dna of george floyd? >> i heard that, yes. >> presumably the pills were not in there prior to mr. floyd being in the squad car, right? >> i assume not, yes. >> so you understand they were tested, appeared to be partially ingested or dissolved? >> okay. >> so there would be evidence of acute ingestion of fentanyl and/or methamphetamine at the time mr. floyd was in the backseat of the squad car?
right? >> they are not necessarily fatal overdoses, they were cases from medical examiners we found fentanyl in their blood sample but they could happen homicide or other drugs involved so they were just random fentanyl concentrations. >> catch you. >> -- somebody may have been shot and killed as a result of a gunshot but as a result of the autopsy process, they collected the blood analyzed the blood as part of the normal autopsy process? >> correct. >> the cause or manner of death in a gunshot wound, homicide, we still look at the blood. >> is. >> a total of 19185, right? >> correct. >> when the slide says 19185
apparently i printed it and started working on my preparation and apparently i received an updated copy of this presentation and its 49623 so it's like 17 page later when trying to verify when i received it because i was using this in preparation of this was all last night. >> was all provided, i'm not sure if it's the same batch that went out but obviously the witness made updates, an updated slide for the jury. >> i understand, mr. nelson has an earlier version, the updated
version. >> show the updated version. >> correct. >> when was the updated version sent? >> the same day as the original -- [inaudible] [inaudible] >> we are going to just take our break. there's a lot of moving parts, i don't think anybody -- we can just acknowledge, without showing it again, you've shown earlier versions. >> fine and part of the problem we are experiencing here, i'm getting many of these items in pdf format, some are electronically from so many
people involved, getting things in different formats so if i could have a second. >> yes, it seems like a good, nobody should be criticized oregon, just tell the jury this is what it is. >> i could provide an extra copy and read publish the slides presented we want to make sure we are not presenting information that's inaccurate. >> it is my fault, your honor. [inaudible] >> i must have looked and assumed it was a second copy of the same thing. >> tell them you were relying on an earlier version of the one
>> i specifically chose the subgroup that was peripheral blood, at the end cardiac blood inflates, wanted to do something that represents most accurately what might be found in a living subject. >> so you were looking and focus specifically on the concentrations in the most equivalents type of blood sample that was taken? >> to the extent you can do that
yes. >> but in in the 19,185 case, not all of them represent a fatal overdose, correct? >> that is correct. >> of the 19,185 cases, do you know the number of cases that would be attributed to overdose specifically? >> unfortunately we don't because we don't get the history of of a lot of the cases, what the outcome was or even in context. >> so you can't determine which of these cases, include something like a gunshot or include something like a heart attack or something else that would cause the death, right? >> that's correct. >> these are simply blood samples? >> correct. >> when you look at these blood samples you say the mean level of these samples was 16.8 nanograms per milliliter, right? >> yes. >> when we save and mean level you're talking the average?
>> right. >> if you take all of the 19,185 cases, add up their levels and divide them by the number of cases, that's the average? >> correct. >> and the median being ten nanograms per milliliter? >> yes. >> meaning that's just 50% of the cases have higher that no levels and 50% of lower, right? >> yes. >> we can't differentiate what the actual cause or manner of death and in one of these cases? >> that is correct. >> now, in terms of the 19,185 5 cases when you're looking at the inclusion of fentanyl versus the exclusion, the vast majority of those cases included it, right? >> picket. >> 15,455 15,455 of the 19,185 cases?
>> that is correct. >> now when you look at the dui concentrations, obviously people, this is a bit of a different type of the situation, right? >> people are alive. >> yes. >> driving a motor vehicle, right? >> yes. >> presumably. >> or sleeping in one. >> i suppose. >> and here again there were 2345 dui cases, right? >> yes. >> the average level was 9.59, right? >> yes. >> and the median level was 5.3 comps of 50% above 5.3 5.3, 50% below? >> correct. >> nonetheless they were all arrested for dui, right? >> well again as an agent of the drugs may be present so this is just looking at fentanyl. >> so what were really doing is we're trying to isolate and create some form of the
comparison of mr. floyd's fentanyl levels to some sample of population, right? >> correct. >> one sample a of populatione know is alive, right? because her driving a car any other sample we have no frame of reference did they die from fentanyl overdose or did they die from some of the reason there's no context? >> that's correct. all we know is they are decease deceased.
>> in terms of women look at the ratio of fentanyl levels between nine and 13 nanograms, right, of the 19,185 postmortem cases, 3088 of those cases had a, again, a similar fentanyl concentration to mr. floyd, right? >> yes. >> again of the 3088 cases within that range, we have no frame of reference, no context as to what percentage of those people died from fentanyl overdose versus some other cause or manner of death? >> that is true. the only thing we have is a similar concentration. >> and so statistically kind of speaking, it's fair to say that some of the 3088 people in that
category died of fentanyl overdose? >> yes. >> and some percentage died at some other cause? >> yes. and again in terms of the amphetamine, methamphetamine and the amphetamine, methamphetamine and fentanyl, do you find that to be an unusual mixture of controlled substances? >> i'm not very familiar with what combinations are being seen with street drugs, so we see a variety of controlled substances. we tend to see that no more with cocaine and heroin then methamphetamine but that's just what i see. but it can't speak to what is regionally being observed. >> have you heard of the phrase
goofball or speedball? >> i have heard of speedball come yes. >> speedball usually being like a fentanyl, an opiate and cocaine, right? >> yes. heroin and cocaine. >> but you've never heard the term goofball? >> no. >> now again this particular case your lab also tested the tools that were found in the squad car as well as in the mercedes-benz? >> yes. >> and you reviewed those? >> i have not. >> but similar to fentanyl and norfentanyl you've got methamphetamines which is the active ingredient, right? >> yes. >> and amphetamines which is the metabolism, right? >> in a tablet are you think? >> know, in mr. floyd's blood sample. >> yes, that was methamphetamin
methamphetamine. >> i and just generally speaking, methamphetamine is the active drug and amphetamine is the metabolite of that drug? >> metabolite but also active. >> okay, meaning dash of what you mean it is also active? >> it's an active metabolite. it also has effects. >> so a person would have an effect from both of those substances? >> correct. >> meaning and intoxicating effect? >> not necessarily. >> but some affect. >> some effect. >> relevant to the dui population, mr. floyd's amphetamine and methamphetamine ratio was on the low side, right? >> so we didn't look at the ratio of methamphetamine -- the amphetamine with mr. flynn
because it was below the reporting limit. it's not on the report. we didn't report it. >> so you can't compare the ratio, that his methamphetamine level was on the low side? >> compared to the dui population come yes. >> and compared to the dui population as well as postmortem cases again there may have been other drugs as you say on board, right? >> yes. >> i have no further questions, your honor. >> redirect. >> dr. isenschmid, you were askd some questions about your lab and the testing that was performed in conjunction with accreditation standards. you remember those question? >> yes. >> you asked by the medical examiners office to perform the
testing in this case, it's at right? >> correct. >> and you perform the testing that was requested? >> yes. >> did mms follow all the standard operating procedures way came to the testing? >> we did. >> you did reporting feeling in your final report that was below the reporting limit, correct? >> no. >> but you maintain that date in connection with your standard procedures come is a right? >> yes. the data shows what we found. >> why do you do that? >> excuse me? >> why do you keep that data? >> because we keep that in the normal course of business. >> is that important up a record of the testing you did everything she went through to achieve a result? >> absolutely. >> you also asked questions about the methamphetamine level that mr. floyd had in his system. you indicated it was a low level, 19 nanograms per milliliter? >> yes. >> solo in fact, you wouldn't expect to feel and intoxicating effect from that level, would you?
>> i would not. >> solo as part of your lab procedures you want to will it it's not just a contaminant, that's how low it was, right? >> i wouldn't say that. it's a very and it was confirmed. >> it was confirmed part of the cooperation process was the amphetamine support it was not just a contaminant come is at right? >> that's true. >> but either way is to floyd's methamphetamine levels were lower than 94% of the driving under the influence population comes to methamphetamines? >> yes. >> you also asked questions about fentanyl levels in this case -- were asked. obviously dependent and you described earlier depending on an individuals tolerance level of 11 nanograms per milliliter have different effect on a different person, different people depending on the level of tolerance, is that right? >> yes. >> in your experience with respect to recent or -- sorry,
fentanyl use, there are a number of cases where you would expect to see no norfentanyl, is that right? >> yes, we do observe that in cases where we know it's something is a toothless it was somebody who dies with its range in the arm or something like that. >> if someone dies with a syringe in their arms you would expect there to be or no norfentanyl? >> correct. >> why is that? >> it gets a very acute amount. it doesn't mean you could never find it because they could be previous fentanyl used but that's not a general observation. >> the ratio becomes important is that right? >> correct. >> why is the ratio important? >> because that basically documents how acute the fentanyl was relevant to its being broken down to norfentanyl. >> so mr. floyd's ratio of 1.96, 11 nanograms per milliliter a fentanyl the per milliliter of fentanyl to 5.6 nanograms per milliliter of norfentanyl supports that there was survival time after the ingestion of
fentanyl, is that right? objection. >> sustained. >> what does that ratio show you? >> it shows two things, that it was survival time from an earlier does or that it could be an additional dose on top of that previous doses. >> and again the ratio is consistent and lower than the average ratio that you see for driving under the influence cases with fentanyl on board, is that right? objection. >> sustained. [inaudible] >> what does that show you compared to the driving population? >> it delineates the difference between a population where a postmortem population where fentanyl is more likely to be acute than in the driving population which more likely to be chronic. >> in terms of the ratio was mr. floyd's ratio more sober to the driving population or people who are allies or more similar to the postmortem population where people were dead.
>> more similar to the dui population. >> nothing further. >> okay. when we don't know the context of how people actually died. >> because us to look at a large number of data within that population. >> so you have no frame of reference though in terms of what is complected the person actually died from. what if of the 19,185 postmortem cases, 19,184 of them were gunshots? >> that's not a possibility but -- >> i have nothing further. >> thank you. you may step down. our next witness we will try to fit in.
i appreciate your patience in staying until 515 thymic if possible because the witness has a flight out tonight so we're trying to finish it tonight. ms. blackwell. >> thank you honor. the state will call dr. william smock. .. let's start out having you state and spell your name. >> dr. bill smock, b-i-l-l
s-m-o-c-k-. >> good afternoon, dr. smock. can you tell us your area of specialization. >> i'm forensic medicine. >> can you tell us what is forensic medicine? >> yes, forensic medicine is legal medicine, taking medicine usually practiced by the forensic pathologist, in my case practiced on living patients and applying that to legal situations. >> could you give us a brief overview of your background in medicine. >> obtained a degree in louisville and entered medical school, 1990 from the university of louisville and then a three-year residency in emergency medicine at university of louisville. then completed a one year fellowship in clinical forensic medicine with the kentucky medical examiner's office.
>> have you ever worked in an emergency room, in emergency medicine? >> yes, many times, many years. >> how many years, doctor? >> 21 years at the level one trauma center at the university of louisville and then moonlighting in smaller e.r.'s. >> what is a level one trauma center? >> a level one trauma center is the american college of surgeons criteria saying this is the place you want to go when you have major trauma. gunshot wounds, car wrecks, stab wounds, strokes, heart attack, this is where we have physicians on duty in the e.r. 24/7 ready to take care. >> are there any level one trauma centers in minnesota that you're aware of. >> there's one right here, sir, in minneapolis. >> hennepin county medical center? >> it is, sir. >> do you also teach in the area of emergency medicine? >> yes, sir, i do. >> what do you teach and where? >> i teach emergency medicine residents, medical students,
paramedics, police officers, not only at the university of louisville, at the louisville metro police department and police academy. i've trained the paramedics for the jefferson town emergency medical service. i also train and teach all over the country in areas relating to strangulation, gunshot wounds, emergency medicine, forensic medicine. >> i was going to ask whether you had any special background or expertise in either asphyxial death or strangulation? >> both, sir, asphyxial, asphyxia, low levels of oxygen in the blood in people that have died and not died. >> do you have any books? >> i've edited four textbooks. >> i won't read them, but, one,
domestic violence and nonfatal strangulation assessment? >> that's one, sir. >> and is this a teaching book? >> it is. it's designed to -- it's a work book where you work through case studies looking at the injuries, understanding the injuries, how the injuries occur, or don't occur, in nonfatal strangulation. >> another one called "forensic emergency medicine", that's correct, sir, that's the second edition of that book. >> and the third larger one, "forensic medicine clinical and path logical aspects". >> that's correct, sir. >> what is this text for? >> that's looking at clinical forensic medicine, which is forensic medicine, but applied to the patient that is still alive in most cases. >> dr. smock, do you have also
have in your background any work as an assistant medical examiner? >> yes, i do. >> what is that, sir? >> louisville, kentucky, we started the program through the medical examiner office, providing living forensic medicine consultations, the same level of evaluation on someone who they've been shot, stabbed, but didn't die in the emergency department and the icu, compared to someone that may have died, given that same level of care. so, that program was started at the kentucky medical examiner's office back in 1990, and from 1991 through 1997, i was an assistant medical examiner at the kentucky medical examiner's office providing those sorts of consultations and evaluations. >> and you have clinical
background? >> yes, clinical forensics is applying the same forensic training that the pathologist gets from autopsies and medicine, applying it to the patient in front of you that's still alive. and so, what is the difference between someone who has sustained a gunshot wound in someone who is dead versus someone who is alive. what did the bull hit? did they survive? did they get to the operating room in time, but the forensics is the same, how to determine exit from entrance, how far was the gun away from the body when the gun was shot, and it's the same science, but applied to the living science. >> dr. smock, how are you currently employed? >> i am the police surgeon for the louisville metro police department, as well as the medical director for the training absolute for strangulation prevention. i'm also the medical director for the jefferson town emergency medical service and a clinical professor of emergency medicine at the university of
louisville. >> could you give the jury some sense how large the louisville police department is, mayor comparison to the minneapolis police department? >> the louisville metro police department we have space for 1200 sworn officers. we're down to probably a little less than 1100 officers right now. i think minneapolis may have 7 to 800. i'm not sure. i think we have a little larger department than minneapolis. >> so would it be fair to describe you as a police surgeon? >> that is my title, sir. that is my role. that's my job. >> and so what are your duties as a police surgeon? >> it varies from day-to-day, they're multiple. it's the doctor that goes with the s.w.a.t. team when the team deploys to make sure if someone gets hurt, suspect, hostage, officer, that there's a doctor there to take care of them. i advise the police chief on health care policy. i do occupational medicine looking at the officers when they get hurt, fitness for
duty, when can they go back to work, write some prescriptions, antibiotics, viagra and most the time it's spent doing living forensic consultations, which means when a call comes, doc, we've had a shooting or internal affairs, we've had an officer-involved shooting, i would go to the scene, to the hospital, wherever that examination needs to be done and do the assessment head to toe, just like a pathologist would do on someone that's deceased, but doing it on someone that is still alive. >> do you actually do police training? >> i do, sir. >> what kind of training? >> i get-- each recruit class i get four hours of training with each recruit class that comes through, two hours is spent on the forensic evaluation of gunshot wounds, two hours is spent on traininglation, asphyxia, elder abuse and child
abuse. >> have you treated persons with cardiac emergencies? >> oh, yes, pre-hospital and in the emergency department. >> what about dealing with patients who struggle with either methamphetamine or fentanyl addictions? >> very frequently, either on the scene or in the emergency department. >> doctor, are you familiar with the symptoms of overdose for either fentanyl or methamphetamine? >> very familiar, sir. >> can you tell us what narcan is? >> na can is an aganist that will block the opioid on the receptors in the brain. so if you overdose and you've taken too much narcotic and you are not breathing or you're close to going unconscious, fw you give this narcan, we give it intranasally, then that
reverses it and replaces the narcotic in the brain and you wake up. >> have you had to make decisions about administering narcan for either methamphetamine or fentanyl? >> you administer narcan for fentanyl because it's an opiate and that's what it reverses. yes, i've administered narcan hundreds of times. >> one of the things i'd like to talk with you about with respect to mr. floyd is drug tolerance. is this the subject of opioid toll raps something you're familiar with? >> very familiar. >> can you tell us drug tolerance? >> the body repeatedly sees a certain drug, most common we think of that is alcohol. does somebody build up a tolerance, meaning at one time you're a naive drinker, you take one sip, one bottle,
whatever, you feel it. but if you're an alcoholic, you feel nothing because that is tolerance. and the same is true or amphetamines as well as for opiates for fentanyl, whether you're talking percocet or other opiates it takes more of that drug to perceive the feeling or high you get when you take that drug. >> somebody who doesn't drink may feel the effects of one beer. >> absolutely. >> and with an alcoholic who knows? >> it may take multiple beers. >> doctor, just for the jury when you made reference to a naive drinker, would you explain what you mean by that because-- >> yes, naive means somebody that doesn't drink, or doesn't do any sort of drug. naive means you're totally new.
>> so, doctor, you've been retained by the state of minnesota as an expert in this case. >> yes, sir, i am. >> are you being compensated for your time? >> yes, sir, i am and i hope so otherwise my wife won't be very happy with me. >> can you tell us what your hourly rate is. >> yes, the government rate is $300 per hour. >> and so the charge for your time is the government rate? >> that is correct, sir. >> so as part of your work indicates, were you asked to render an opinion regarding the cause of mr. floyd's death. >> yes, sir, i was. >> before we get into your opinions, would you tell us what it is you reviewed to give you a foundation for forming opinions? >> so i reviewed videotapes, body camera videos, bystander videos, police videos, reviewed medical records, pre-hospital records, statements from
witnesses, the autopsy report, autopsy photographs, thousands of pages of documents, sir. >> doctor, before we get to the opinion, there was one thing i meant to ask you and overlooked. as a police surgeon, are you required to maintain board certification in emergency medicine? >> no, sir, i'm not. >> and are you currently board certified? >> no, i'm currently board eligible, taken boards on two occasions since i'm not in the emergency department anymore and not required for the police surgeon, i'm no longer board certified. >> ever you been in the past? >> yes, sir, on two occasions. >> so, doctor, let's talk about your opinions regarding the cause of mr. floyd's death. >> yes, sir. >> you formulated opinions. >> yes, sir, i did. >> would you tell us what your opinion or opinions are? >> mr. floyd died positional
asphyxia which is a fancy way of saying he died because he had no oxygen in his body. >> referred to as low oxygen. >> low oxygen is one way. no oxygen. when the body is deprived of oxygen and in this case, from his chest, pressure on his chest and back, he gradually succumbed too lower and lower levels of oxygen until it was gone and he died. >> did you consider other possibilities as causes that you evaluated and dismissed as unlikely? >> absolutely. >> was one of those excited delirium? >> yes, sir, it was. >> would you first tell the ladies and gentlemen of the jury what excited delirium is? >> excited delirium is a physical and psychiatric state where because of an imbalance in the brain a patient will
exhibit multiple symptoms, basically they are hot, their body is revved up, heart rate is up, respiration is up, super human strength. they are out of control. their speech is garbled. it doesnt make sense and delirious, someone who is delirious. i'm very familiar with not only in hospital, but pre-hospital the symptoms of excited delirium. >> doctor, let me show you what's marked as exhibit 921 for identification purposes. i want to show it to you and then let me ask you a couple of questions. >> is this a demonstrative you
created showing the 10 signs of excited delirium? >> yes, sir, it's from the american college of emergency physicians white pages. >> is excited delirium considered a controversial diagnosis? >> yes, sir, it is. >> why is that? >> because there are varying opinions as to what causes it, what is it, . forensic pathologists, emergency physicians, there isn't 100% agreement on what excited delirium is, but i can tell you at least in my opinion, i think it is real. >> but are there any reputable organizations that do not recognize it? >> that's correct, the american medical association does not recognize it. the american psychiatric association does not recognize
it. >> so, your honor, i offer exhibit 921 for demonstrative purposes. >> any objection? for demonstrative purposes only and not go back to the jury for deliberation. >> and i've gone back to manage to scratch on the screen. if your honor could-- thank you. so if we could, walk through each of these and we'll go through them one by one and i'd like with each one to explain what it is and then explain how it applies to george floyd. so let's start with the number one, inappropriate clothing, naked or partially closed. what is the significance of this one? how does it manifest? >> when we get a call, a naked man in the street, first thing i'm thinking is excited delirium.
why? why would somebody take off their clothes? their body is hot. so in the case of mr. floyd was he appropriately dressed or inappropriately dressed for the weather? and in the case of mr. floyd, i think the temperature was in the 70's and he is appropriately dressed. so therefore, this does not apply to mr. floyd. >> so what about the second one, attraction to glass, destruction of glass, mirrors, lights on vehicles? >> this is another sign of -- that someone with excited delirium, they're attracted to glass to light, to mirrors. sometimes they will kick, punch, trying to break the glass, break the mirror because some reason their brain says that's a threat to them. when you watch the video of mr. floyd in the store, glass all around him. was he attracted to any glass
on the counter in the windows? no. so in mr. floyd's case, it doesn't apply either. >> so you eliminated the second one? >> yes, sir, i did. >> what about the failure to respond to police presence? what does that mean? >> that means when an officer gives you a command to do something, you don't even hear it. you're going on. when we watch the video of the officer asking mr. floyd to go to the sidewalk, sit down, does he comply? absolutely he complies. does not apply to mr. floyd. >> because you saw him being responsive so the police. >> he was responsive, giving appropriate answers. >> number four, constant or near constant physical activity. what does that mean? >> that means these individuals are sped up. their body is going 90 miles an
hour and in in case, what did we see mr. floyd do? he sits down. he's able to sit down and he's not going 90 miles an hour. his activity level isn't constant. so, you can cross that one off the list. >> you saw no evidence of it? >> i'm sorry? >> you saw no evidence of it? >> i saw absolutely no evidence of it, sir. >> at tiring with heavy exertion? >> once again, these people can run a marathon. if you have officers chasing them, they can go and go and go, why? because they're sped up. in this case, did we see mr. floyd tired? absolutely we saw him tired, tired to the point where he stopped breathing. does it apply in this case, no, it does not. >> number six, unexpected or
unusual strength. >> these people are described as having super human strength. they're throwing police officers off right and left. somebody my size is throwing people off right and left. what do we see in this case? is mr. floyd able to throw those police off that have him on the ground? no, he does not. so in this case it does not apply. >> number seven, unaffected by pain. >> when we listen to the tapes, do we hear mr. floyd complain of pain? absolutely do. pain in his neck. pain in his face. pain in his back. he's complaining of pain. so, does this apply to mr. floyd? absolutely not. if mr. floyd did not complain of pain, we could add it into the list, but in this case, he's complaining of pain from the time he gets on the ground. does not apply.
>> number eight, very rapid breathing. >> these individuals will have a breathing rate 30 to 40 times a minute. very rapid breathing. when i watched the videotape and counted mr. floyd's respirations at different points, it was at one point it was zero, but the other times it's 15 to 20, 22, 23 in that range. by breathing criteria, he does not meet the excited delirium criteria. >> what about number nine, excessive heat or hot to touch? >> a couple of ways to assess this and did you see evidence of excessive sweating? what did the emergency -- the e.r. docs describe when mr. floyd presented to the e.r.? he was cool to touch. when these patients come into
e.r., their temperature, they're hot, can be 104, 105, 106, even 107 degrees, temperature, mr. floyd was cool to touch. does not apply. and then the excessive sweating, number 10. >> and again, because when your body gets hot, when your temperature goes up, what does your body want to do? it wants to sweat to cool you down. when i watch the video do i see evidence of sweating on mr. floyd? no, it's not there. so, again, does not apply. >> so, doctor smock, if we have to have a minimum of six of these items, six of 10 for excited delirium, how many did you see? >> zip. >> all right. so i want to talk with you about another potential cause for death that you may have considered i think eliminated, which is drug overdose. >> yes, sir. >> are you familiar with the toxicology results in this case? >> yes, sir, i am.
>> just to remind us, what were the levels of fentanyl and methamphetamine in mr. floyd's blood? >> yes, the autopsy report is here. the fentanyl level was 11, the metabolites, 5.6, the methamphetamine, what the lab uses. >> when focusing on fentanyl you have lots of experience treating patients suffering from opioid use? >> yes, i do. >> could you explain how that might differ from fentanyl overdose? >> the fentanyl-- let's kind of work backwards. with fentanyl overdose, because it's a narcotic, in excessive amounts it can kill you because it will cause your respiratory
rate to go to nothing. that's how you die with a narcotic overdose, you cease to breathe. with fentanyl toxicity, you're looking at somebody who is high, who is awake, but they're high. there's a big difference. how do you fentanyl intoxication, or fentanyl overdose, are they breathing, talking normally or getting sleeping, the respirations getting less or not breathing at all. that's how you differentiate, just by looking even without a lab report look at what that patient is doing. >> so in the case of a fentanyl overdose, are there certain telltale signs of a fentanyl overdose? >> yes, they are-- people can be constricted and they're snoring, their
respirations are decreasing or they're not respiring at all. >> now, bringing us home to george floyd. when they came to the scene on may 25th, the paramedics, do you recall whether his pupils were constricted or not? >> i believe they were dilated. >> do you know what the concept of air hunger is? >> yes, sir, i do. >> would you tell us what that is? >> air hunger, the best application is you are wanting to breathe. for some reason, one example would be if you're drowning, you're going to do everything you can to get to the surface of the water because you want to breathe. another application that i frequently deal with is someone who has been strangled. when their airway has been cut off and they can't breathe, their body is telling them to
breathe, but they can't because of the pressure on their airway, that is hunger, that is the human desire to live, to breathe. >> so when george floyd is saying, please, i can't breathe, i can't breathe, is that an example of air hunger? >> that's an example of air hunger. >> would you tell the ladies and gentlemen of the jury, whether fentanyl overdose causes air hunger? >> no, it does not. the only time it could is if you've overdosed, but it's not air hunger you're going to sleep. are a he not hungry at all, you're sleeping. there's a difference between air hunger, the drive to bring in that air versus an overdose. >> with an overdose, if it's not air hunger that fentanyl causes, does fentanyl diminish the drive to breathe at all? >> in a-- by therapeutical--
it can drive if you have too much. >>, but you're not starving for air? >> you're not starving for air. >> doctor in the case of a fentanyl overdose, you talked about a person going to sleep or snoring either. before death due to fentanyl overdose is a coma state reached? >> yes, you -- someone who is asleep, you could say they look like they're in a coma state. they're not moving. so, that's what you would see with an overdose. >> you've watched the various videos with george floyd's encounter with the police on may 25th? multiple times. >> can you tell the jury from having looked at those videos, can you tell by looking at that alone whether george floyd was suffering from a fentanyl
overdose. >> he is not. when you watch those videos and we go through them, what is his respiration? he's breathing. he's talking. he's not snoring. he is saying, you know, please, please get off of me, i want to breathe, i can't breathe. that's not a fentanyl overdose, that's somebody begging to breathe. >> and so if a person is suffering from a fentanyl overdose, would you describe that person then as alert? >> no, sir, they're not going to be alert, they're going to be sleeping. >> would you describe them as oriented? >> no, they're going to be -- their brain is going to be in sleep mode or not breathing mode. >> was george floyd oriented? >> he was, he gave appropriate
responses. name, date of birth. >> he knew what was happening? >> he knew and he responded appropriately to the questions asked of him. >> have you ever encountered a situation of a fentanyl overdose where the person was in the overdose displaying air hunger, and essentially crying out for their life or crying out in pain? >> no, sir. >> now, did you, from your review of the medical records and other data in the case, get some sense of what mr. floyd's history was with respect to opioid use? >> yes, sir, i did. when you look the at medical records, mr. floyd has been a chronic user, meaning what i saw was for years. >> and how would this correlate to the notion of tolerance we talked about at first? >> the more you use any drug,
alcohol, in this case fentanyl, you build up that tolerance so it takes more drug to give you that high. to affect your brain. and in this case, we actually had a visit to the emergency department where he took seven or eight narcotic pills, they watched him and let him go. >> was there any use of either oxycodone or percocet that might be relevance to the question of tolerance. >> when he presented to the emergency department he said he might have taken percocet or oxycodone. >> what does that have to do with tolerance to fentanyl? >> they both -- both fentanyl and oxycontin, percocet, oxycodone work on the brain, a
receptor, they both attach to and stimulate that receptor. this is what we call cross tolerance. if they both work on the same receptor, either one is going to give you an effect doe penning on the quantity that the brain sees. >> in terms of the population you treated in terms of opioid issues, are you able to characterize what the range of the opiate levels have been in living patients? >> yes, i have, sir. >> what can you tell us about that? >> what i've come to, in clinical practice is, you don't rely on the level to tell you how much it's impacted a particular patient, you look at that patient because i've seen patients they could have low levels, but i've seen patients with fentanyl levels, 100, 120, 140, and they're walking and talking. so the level says yes, it's
there, but based upon their prior history of use, chronic use, does that particular level affect them or not? >> so how relevant then was the level of the methamphetamine found in mr. floyd's blood to your analysis of the cause of death? >> methamphetamine or fentanyl? >> methamphetamine. >> with methamphetamine it's really a nothing level. it's a level you expect to see with a recreational use of methamphetamines. and clinically, that's an extremely low level. >> so, i want to switch topics and talk about the cause of death you did find related to asphyxia or low oxygen. >> yes, sir. >> are you familiar with certain myths that exist around
the indicator for death by asphyxia or low oxygen? >> yes, i am. >> do you teach your students with regard to some of the myths? >> yes, because strangulation is a storm of-- is a form of asphyxia, this is part of classes i teach, strangulation, asphyxia, what you see, what you don't see. why you see something and why you don't see something. >> for example, in your teaching of your students, what do you teach them regarding inferences that can be made by the presence or absence of bruising on the body in autopsy? >> bruising, you can be fatally strangled, die of asphyxia and have no bruising. the presence or absence of a bruise on a human body is dependent upon multiple different variables. how much pressure is applied,
how that pressure is applied. how frequently is that pressure applied and the example i like to use, you can have someone put your biceps and forearm on either side of your neck and squeeze and render you unconscious or even kill you and you'll never ever see a bruise on the neck. the reason is you're applying a broad surface area, bicep and forearm to a broad surface area. if i were to take this lanyard and pull it around somebody's neck and pull tight, i'm putting the same amount of pressure in the smaller area and i would expect a ligature mark. there's variables that dictate whether you have a bruise or you don't. condition of health, medications that cause you to bruise easily, aspirin, other
medications. so you can be, that's the-- you have to have bruises to prove strangulation? no, you don't. you can be strangled to debt and have no bruises. so, that's one of the big myths. >> all right. dr. smock, can you tell us what a petechial hemorrhage is? >> yes, petechial hemorrhage is a ruptured capillaries. they come from the rupture of the capillary beds. they're popped. i like to think of it as a little water balloon and what happens when i put too much water into a balloon, it pops. what happens if i put too much blood into a capillary? it pops.
>> so, what does the presence or absence of petechial hemorrhage tell us about whether a person did or did not die of asphyxia or low oxygen? >> it tells us nothing because in order to create that ruptured capillary two physical things that have to occur in the human body, one, i have to have the venous return, in the case of the neck the jugular vein blocked. how does that happen? well, i'm putting pressure on the neck. the second thing that has to happen, i have to have blood still being pumped into the area of the body, that capillary bed. so, if both those two criteria aren't met, blockage of a vein with blood continuing to be pumped in, i will never ever get a petechial hemorrhage. so you can be fatally strangled and not have petechil
hemorrhage because if the two physiological criteria aren't met, it will never happen. >> so, doctor, i want to show you a few of the video clips as relates to your conclusion that mr. floyd passed away from asphyxia or low oxygen. so i want to play the clip and then tell me how it was significant to are decision making. so if we could pull up exhibit 127 already in evidence, at 20:21. yes. stopping at 20:21, i'm sorry, bret. starting at the beginning. >> on the ground, on the ground. [inaudible]
restraints-- >> i can't breathe. >> i can't breathe. i can't breathe. i can't breathe. >> stop moving. >> mama, mama, mama, mama. >> one of the front pouches on my right side bag. >> mama, mama. >> all right. oh, my god. i can't breathe. i can't breathe. i can't breathe, man. mama, i love you. i love you. i love you. >> so this is the segment. dr. smock, that you listened to and observed? >> yes, this is one of the segments. >> why is this relevant to your assessment? >> what's important to the
assessment is what's happening over the entire length of the video. in particular this first section what we're looking at is listen to mr. floyd's voice. he's speaking with full volume. and then i want you as we go through these different segments, compare what we're hearing now to what we hear later, how his voice changes. >> please, finish your answer. >> i also want you to look at the positioning of mr. floyd, where is he? where do we see pressure being applied to his neck, to his upper back, to his lower back. what's also very important is, as this progresses and you know, this is -- this is a progression over, you know, four and a half, five minutes of mr. floyd gradually decreasing his ability to
survive and what you'll see and this is a great, i don't know does this work circle? >> yes, it does. >> what i want you to also watch for is what is his right arm doing as this progresses. you will see him pushing against the tire. you'll see his right arm, his elbow pushing against-- >> [inaudible] >> well, i'd like to know you circled an area on this exhibit. what? >> i'm sorry, judge. >> go ahead and ask the question. >> yes, i'd like to know what is it showing us? why is that significant? >> this is very important because it's showing what mr. floyd is doing to try and breathe, to get his right side of his chest up off of the pavement so he can bring in air. >> so let's look at another segment, if we can start at
20:21. >> i can't breathe, i can't breathe. [inaudible] i can't breathe. >> what do you want? >> i can't breathe. the i can't breathe. >> get up, get in the car, man. >> i will. >> get up, get in the car. >> i can't breathe. >> get in the car. >> get up. >> mama. >> i can't. is that-- my neck. [inaudible]
[inaudible] >> so, dr. smock, as you listen to that segment, that's one that you chose to play for the jury, what was significant about that? >> what we're seeing, again, and if you're listening his voice is now getting gradually weaker as we're going through this. he is telling the officer, i'm about to die. i am through. he's watching his body move, turning his face into the pavement to try and get more oxygen in. this is the progression as we go step by step and deeper into lower levels of oxygen in mr. floyd's blood. we also have -- and using his elbow to try and leverage his chest up.
>> so, doctor, in addition to the subdue under restraint there on the street in the video, was there other evidence, including physical evidence that supported your conclusion that mr. floyd died of low oxygen or asphyxia? >> yes, as -- i think probably in the next section as we go through, you will hear his voice get weaker and weaker, and you will see his-- lose facial expression. you'll hear him make sounds of trying to breathe get closer. he then goes up conscious. you will then see in the next section he he has what's called an anoxic seizure, a fancy name
for oxygen is low, legs shake and you can hear the handcuffs shaking and see the body camera shaking when he has an anoxic seizure farther down the line. >> were there physical injuries that you see to him, dr. smock. yes, his left shoulder was ground into the pavement from the pressure from behind. the left side of his face had deep abrasions from his face being pushed into the pavement. >> so, in the interest of time this afternoon, i won't show the additional video, dr. smock, and i want to ask you about a different subject and that relates to cpr. could you tell us about the importance of timing with respect to performing cpr? >> the sooner we start
compressions and ventilations, the higher more successful our resuscitation rates will be. >> at what point should cpr been frchld on mr. floyd. >> way before when he was unconscious he should have been rolled over. we have documentation on the video that the officer says, i can't find a pulse. why -- and that's clearly, but when you look at the video it should have been started way before, should have been rolled over, checked his respirations, but clearly, when they can't find a pulse, cpr should have been started. thank you, dr. smock, no further questions. >> mr. nelson.
>> >> good afternoon, dr. smock. >> good afternoon, sir. >> thank you for being here with us this evening. sir,you say you're not a pathologist? >> that's correct, sir. >> you're not trained in and tomorrowic pathology? >> no, it's part of my forensic training, but i'm not and don't can consider myself an and tomorrowic pathologist. >> and you're not trained in forensic pathology? >> i was trained by forensic
pathology that's part of my training, yes, i'm trained in forensic pathology as applies to the living patient. >> and you're not board certified in forensic pathology. >> that's correct. >> you practice emergency medicine. >> yes. >> and you have something you describe as forensics for the living? >> that's correct, sir. >> do you, in addition to your practice stay abreast of the medical literature in terms of forensic pathology? >> i do get the journal of forensic medicine, sir. >> and how many autopsies have you performed? >> physically performed as what's called the dinar, a hundred, how many have i attended? thousands. >> you would fwree agree that methamphetamine and fentanyl
when combined produces a different result? >> they may depending on the level and the individual. so there are variables, but essentially methamphetamine and fentanyl combined is different than a reaction to fentanyl? >> that's correct, sir. >> all right. and you would agree that in emergency rooms of late, the number of deaths related to the methamphetamine and fentanyl combination have increased? >> i can't speak of at late, but it wouldn't surprise me, sir. >> all right. and that type of a death, methamphetamine and fentanyl is a much different type of a death than a simple fentanyl-- not simple fentanyl, but phentinol exclusive death. >> depending on the
individual. >> there's no safe level of amphetamine? >> no, there is a safe level of amphetamine, people with add. >> but in terms of street purchased methamphetamine, there would be no valid medical basis to have that in your system? >> that is correct for methamphetamine. >> now, you talked a little about the coma state in overdoses that you would expect. what's the duration you would expect to see of a coma state in a fentanyl overdose? >> that depends how much fentanyl is in that individual's system, how quickly do we get narcan on board. multiple variables, sir. >> lots of variables. you talk about positional asphyxia and you've reviewed the autopsy. did you see any medical autopsy or physical-- excuse me any physical evidence
from the autopsy that can point to mr. floyd's airway being obstructed? >> no, sir, not in the autopsy. >> and while mr. floyd initially was on the ground, he was talking, right? >> yes, he was, sir. >> at points raised his head, agreed? >> yes, sir. >> and he for some period of time was alert, correct? >> yes, sir, he was. >> he was coherent as you described and he was making sense. >> yes, sir. >> what is the evidence found at autopsy of significant force that was used to keep him in the prone position? >> the evidence was not at autopsy. it is on the videotape, sir. >> okay. you were talking about how mr. floyd maintained or stated that he could not breathe while in the prone position? >> that is correct, sir.
>> he stated that before ever being in the prone position as well, correct? >> that is correct, sir. >> several times, correct? >> that is correct, sir. >> at that point when he stated that he can't breathe and he's in the back seat of the car, there is no one on his back, is that right? >> that's correct, sir. >> and do you know if there was anything such as a fentanyl. >> no, sir. >> you've prepared a report and suggested that partial pills were in the back of the squad car and they contain mr. floyd's dna. >> yes, i was.
>> an and methamphetamine and fentanyl combination. >> that is correct, sir. >> people who have their respiration suppressed as a full-time of fentanyl don't necessarily all the time die, right? >> that is correct, sir. hopefully they don't-- >> treating people in the e.r., you have treated people with cardiac diseases? >> yes, sir, i have. >> and in terms of your treatment of people with cardiac diseases, have you encountered people who have a combination of methamphetamine and fentanyl? >> yes, sir, i have. >> and obviously, every single
person is unique, correct? >> yes, sir. >> and you've experienced people who have cardiac disease, fentanyl and methamphetamine who pass away? >> yes, sir. >> not necessarily from those but maybe from something else. >> and sometimes it could be just from those? >> it would depend upon the case. >> right. you treat people with covid at the e.r.? >> i don't, but i've treated police officers with covid, sir. >> are you aware that people who are in the icu with covid are often times held in the prone position? >> yes, sir. >> and that actually assists them in their oxygenation, correct? >> that is correct, sir. >> and they don't necessarily suffer sudden death, right? >> that is correct, sir. >> those people may not be moving around very much?
>> during the icu, they're probably not moving around very much. >> methamphetamine certainly has an effect on the heart, right? >> it can, sir. >> i mean, one of the-- you're aware that methamphetamine can be prescribed, correct? >> amphetamine can be prescribed. >> amphetamine can be prescribed. and one of the side effects of the prescription amphetamine, sudden heart arrhythmia. >> that's a rare side effect, but it's certainly possible. >> you talked about the pressure that somebody may -- the lack of bruising, right, as explained by the surface area of the pressure that he is applied, right? >> that's one of the variables, sir, right. >> and a knee has a relatively
small surface area compared to say the entirety of the arm as you described, right. >> no, actually if you think of the size of the knee on the neck, that's comparable, sir. >> and you would agree that in this particular case when you met with-- or you met with prosecutors several times, right? >> yes, i have, sir. >> and you would agree that generally speaking, mr. chauvin did not block both carotid arteries? >> that's correct, sir. >> and he may not have blocked one of the carotid arteries? >> that's hard to say, he could have blocked one of the carotid
ar arteries. >> it could have been a flow, and be difficult to render someone unconscious by blocking one of the carotid arteries? >> if they have collateral flow meaning bloods will go up one of the arteries in the neck. >> in order to render someone by blocking the carotid arteries, you have to block both and when that happens, that happens quickly. >> that's correct. >> less than 10 seconds? >> that is correct. >> you've reviewed the videos many times? >> i have, sir. >> spent a lot of time kind of studying and analyzing the videos? >> yes, sir. >> how many hours would you estimate that you had spent analyzing the videos? >> 10.
>> and you were able to see this incident from multiple different camera perspectives, right? >> that is correct, sir. >> if mr. chauvin's knee was placed at the poterior base of the neck, right, that wouldn't have much effect on his diagram, would it? >> no, sir. >> you work with police officers quite regularly? >> every day, sir. >> and you've-- i'm assuming you've said you've gone to s.w.a.t., s.w.a.t. tactical kind of places, or to arrests? right? >> yes, sir. >> and i assume you have observed police officers use a prone handcuffing technique? >> yes, sir. >> and i assume you've seen
officers use prone-- >> [inaudible] >> within the scope of expertise, but beyond the scope of direct so if you could ask nonleading questions. >> sure. ... you are experiencing accompaniment police officers to various locations you have observed police officers use of prone handcuffing technique? >> yes, i yes, i have for s of time.
>> you've observed them place their knee in the posterior in the base of the neck, right? >> yes, again for short periods of time. >> obviously depends on every circumstance and situation, right? >> i don't understand your question. >> i will withdraw it. was the bruising a mr. floyd's back if you're aware of? >> know i'm not. >> either above the skin or below the skin? >> no, sir there was not. >> there's unquestionable evidence that mr. floyd had cardiovascular disease, , corre? >> that is correct, sir. >> you would agree the pathologist who performed the autopsy found a 90% blockage of the right coronary artery? >> yes, sir. >> your expense as emergency room physician you could refer someone to have a procedure to
open that up, , right? >> if they are exhibiting signs of a heart attack or cardiac ischemia, meaning they are not getting oxygen to that part of the heart. >> that's called a stent? >> that is correct sir. >> the purpose of that is to actually increase or improve the blood flow through the artery? >> that is correct sir. >> when you have a block the vessel, that can lead to heart attack, right? >> it is a block, that is correct, sir. >> lead to a cardiac event, right? >> if it is completely blocked that is correct, sir. >> and when it is not completely blocked it forces the heart to work harder? >> yes, sir. >> oftentimes people go through substantial risks of heart surgery to have that fixed, right? >> they have --
>> partial blockage fixed. >> that is correct, sir. >> you have reviewed all of his previous medical records that were made available to you, mr. floyd's that is? >> yes, yes, sir, i have. >> and high blood pressure from this hospital admissions was noted? >> that is correct, sir. >> there is no dispute that methamphetamine was in his system at the time of this incident? >> yes, he had a very low level. >> methamphetamine increases the heart rate? >> it can, , sir. >> so again it increases this demand on the heart, , right? >> absolutely can, sir. >> if you had -- well, i will strike that. you were aware that mr. floyd had engaged in a struggle with police before he was placed in the prone position come right? >> yes, sir he did.
>> that type of physical exertion also puts a certain divan on the heart, , right? >> it can, sir. >> when you absorb the struggle you could observe his vein pulsing? >> no, sir, i did not. >> that kind of physical exertion of struggling with a couple of police officers, would you say that is similar to something was called a stress test or putting the heart through that physical exertion? >> no, sir that would not be comparable to a stress test. >> what is a stress test? >> a trust status of when you put on a treadmill and you are hooked up to monitors and then you go faster and faster, and then the level of the treadmill can go up and up and up and up. >> so similarly when you are
struggling with police officers, your heart rate is going to go up and up and up and up, right? >> your heart rate but that's not a stress test, sir. >> understood. people have had cardiac arrhythmias during struggles with police before? >> yes, sir. >> what's the physiological mechanism of a person suffering a brain injury from hypoxia? >> when the brain levels of oxygen start going down certain things will happen. their level of consciousness will begin to decrease. when they get to the point where the oxygen level is very low then they will have that anoxic seizure as he saw with the shaking of the lake and the shaking of the wrists, and as
time goes by more brain cells die. for every second the brain goes without oxygen, low levels, millions of neurons and cells will die. so what happens when you get to that state you have brain damage and then if it's not -- whatever the cause is, then you die. >> so then rain damage can occur from low oxygen? >> that is correct, sir -- brain damage. >> when mr. floyd was speaking to the police officers, right, as he was in the prone position do you see any evidence that his brain was injured at that point? >> which part? because he speaks in full sentences or full voice early, but later on his speech is
weaker and weaker until there is no speech. so which window are we talking a? >> at any point when he's speaking with police officers, with or be brain damage at that point? >> not while he is speaking, sir. >> can people suffer brain injuries while there are conscious? >> depending upon the mechanism, stroke would be an example. hit in head would be another example. >> one question i wanted to ask you. you talked a little bit about tolerance, right, and how people
can build a tolerance particularly to opiates relatively quickly, right? >> i didn't say quickly. >> well, people build a tolerance, right? >> yes, sir. >> you're not a toxicologist, correct? >> no, sir i am not. >> but you some general familiarity based on your expenses in emergency room doctor, people who are tolerant to particular substances? >> that is correct, sir. >> when someone stops using a controlled substance for a period of time, that tolerance dissipates, agreed? >> that is correct, sir. >> with certain types of controlled substances tolerance dissipates very quickly? specifically fentanyl. >> i am not familiar how quickly it decreases, or increases. >> so a person's tolerance is a situational, right? let me rephrase. someone who is tolerant, that
tolerance could be built up over an extended period of time, agreed? >> that is correct, sir. >> tolerance come once that come once a person stops using that controlled substance their tolerance dissipates. >> that is correct. >> over some period of time. >> that is correct, sir. >> could be days, weeks, months? >> my experience it's going to be weeks to months, not days. >> so if someone does not using a controlled substance for several months, say two to three months, they are going to lose that tolerance, agreed? >> some part of it they may. depending upon the substance. >> and then if they start using again, right, they're going to start building that tolerance up to some degree? >> that is correct, sir. >> if they had a chronic use for a long curative time they decrease the tolerance to some degree, once the surges again they will not just instantly jump back up to the same
tolerance of? >> your honor, i object to this question, vague. >> overruled. >> yes as -- occurring in the brain as you see different levels that tolerance will change over time. >> right. did you see any evidence in terms of this autopsy or medical records that he had in history of lung disease, mr. floyd that is? >> i believe he had a history of covid. >> other than covid, any other essential he would've had healthy lungs? >> i don't recall specifically any lung disease.
>> but there was evidence of heart disease, right? >> that is correct, sir. >> when someone is experiencing again based on your experience, experiencing and arrhythmia they would also experience that sensation of a shortness of breath? >> it depends on the nature of the arrhythmia. >> when someone is experiencing a heart attack, right, because their vessels are blocked and the stress on their heart is increased when they describe that shortness of breath? >> objection. relevant. >> overruled. >> patients can complain of shortness of breath while they're having a heart attack. that is correct, sir. >> you heard the officers asked -- >> next up we are live at the hennepin county courthouse for the in of the second week, day
ten in the trial of jerk showman, former minneapolis police officer charged in the may 25, 2020 death of george floyd. they should be starting shortly and will have live coverage as we've been doing throughout the day here on c-span2. just from the times and other news horse and get medical testimony will continue today. we are likely hear from the hennepin county medical examiner who did the initial autopsy of george floyd, doctor andrew baker determined during his autopsy that mr. floyd died from quote cardiopulmonary arrest. is expected to be one of the witnesses today, they can of the trial. -- day ten of the trial.
>> when the adjourned for the day, yesterday the judge indicated they would start at 9:15 a.m. central. it's getting about that time. we saw a moment ago and the trial should be getting underway shortly. i remind all of today's proceedings will re-air tonight begin at 8:00 eastern here on c-span2 and all of our coverage of the past two weeks available
at c-span.org. >> we have one issue to deal with this morning we are going to deal with that offer audio and off video but it will be on the record and the press can remain and report on what's going on in the courtroom but it will not be broadcast outside this room. so if we could get the jury for us.
>> you may have heard the judge say they would bring the jury in and the attorneys as well and proceedings will happen now offer audio and off video. it should be fairly brief but the trial getting underway here on this friday, the last day of the week of the second week of the trial of derek chauvin in the death of george floyd.
>> the judge and the jury and the council are in a session offer audio, off video. when the trial gets underway we will have live coverage here on c-span2. until then we will continue to show some of the testimony from thursday. >> just a reminder, doctor, you're still under oath. >> yes, thank you. >> mr. nelson. >> good afternoon, dr. tobin.
>> hello. >> thank you for being with us here today. >> i will take a a sip. cheers. right? >> yes. >> are right. so just want to review a few things with you, sir. i don't think we'll take too long but, so you are ultimately approached by the state of minnesota to assist them in the review of the medical issues in this case, correct? >> correct. >> and you have volunteered to do this work at no cost, correct? >> correct. >> you are not a normally involved in criminal cases of the snake, correct? >> correct. >> this is a first time you've been involved in a criminal case? >> correct. >> it was at reason you decided not to charge a fee, correct? >> correct. >> when you are in other cases what type of feed do you normally charge? >> i charge per hour. >> what is your hourly rate.
>> my hourly rate is 500 and our for the use of material. >> but you agreed to waive your hourly rate for this? >> right. >> you felt it was an important case, right? >> yes. >> in preparation for your testimony today he met with the state numerous times, correct? >> correct. >> you have had the opportunity to review all of the medical information that was obtained in this case? >> yes. >> that would include mr. floyd previous medical history? >> correct. >> the autopsy and attending toxicology reports that were prepared in this case? >> yes. >> as well as some investigative materials, please reports and things of that nature? >> correct. >> just correct me if i'm wrong, but you're not a pathologist, correct? >> correct, i am not. >> your specialty is in pulmonology, critical care, things of that nature? >> correct. >> you also have an interest,
and impressive resume relevant to applied physiology as well? >> correct. >> you have been honored quite extensively for your work in that regard, right? >> correct. >> you are not minneapolis police officer? >> it's fair to say the training that is provided by the minneapolis police department in terms of medical care comes nowhere close to your level of expertise? >> correct. >> you understand minneapolis police officers are not even emts? >> correct. >> they have basic lifesaving certificate dealing with gunshots, tourniquets and cpr? >> yes, right. >> so you've also had the opportunity to review a lot of the body camera footage, correct? >> yes. >> you have done, i think he testified that you watch these videos hundreds of times. >> correct. >> and you've watched them all
from all different angles? >> correct. >> and you had the luxury of slowing things down, putting it in slow motion, still framing various times? >> correct. >> so your analysis of this case comes after hundreds if not thousands of hours of time spent looking at this information? >> i don't know the total amount of time that i spent but it is substantial. >> bright. so then you ultimately, based on the review all of that, you prepared a report? >> correct. >> and you provide it that to the state of minnesota late january of this your? >> january 27. >> and after that you that numerous meetings with the prosecution team in this case? >> by phone or by zoom. >> including january 30 of this year? >> i don't know the date but, i mean, that sounds correct. >> so if i will tell you the dates were january 30, march 3,
march 9, march 17, march 21, april 6 and april 7, you would not have any reason to dispute me. >> i have no reason to dispute that. >> you understand notes are made of those meetings and provided to the defense industry? >> i understood that. >> you've also been able to spend a substantial through to time preparing the exhibits that the jury was able to see earlier today? >> correct. >> those are all prepared by you or someone within your team? >> they were prepared by me. >> you provided those to the prosecution in advance of today's testimony? >> correct. >> you understand those provided to me last night? >> i have no idea when but yes. >> all right. you had a lot of time to prepare both yourself as well as the prosecution team in connection with this case, fair to say? >> correct. >> good morning to her honor, counsead