they can be hard. that's why it's known as hardening of the arteries. sometimes they fracture and you can see clot or fiber, protein of the blood filling that plaque. the plaque went from being smaller to bigger very, very quickly. sometimes you can get hemorrhage into a plaque. the plaque can grow very quickly. we can see that with the naked eye at autopsy. sometimes we see it under the microscope as well. to get to your question, counselor, i didn't see those changes in mr. floyd. these looked to be stable plaque. >> if they had fractured in some way and created a clot of some kind, would that be observable on autopsy? >> yes. it's one of the reasons we dissect the arteries so carefully. you wouldn't want to miss an acute change. that would tell you a lot about

how a person died. >> if there were a thrombus, what would that look like? >> if we find a thrombus, if the person dies quickly, we won't see anything in the heart muscle. people need to survive for hours from their acute cardiac event before we can see changes in their heart. again, if a person dies very quickly from a coronary event, we can only infer what happened based on the fact that they have bad coronaries and the circumstances of their death. we wouldn't expect the heart muscle to look abnormal. >> if the heart muscle shows damage from a clot, what does that look like? >> that depends on how long the clot has been there and how long the person survived. there's a generally good

progression of changes we see very, very early. all you might see under the microscope is some of the heart cells look wavy and abnormal. they take on way more pigment after that. they look much brighter under the microscope. as the heart cells start to die, that necrosis brings in an inflammatory reaction from the body. you see inflammatory cells come in and clean up the dead heart cells. then the body will bring in gran lags tissues. if the person survives, that dead area of the heart turns into a scar. once they die, depending on how long a person survives, we'll see very early changes all the way up to a scar. >> with respect to mr. floyd, you didn't see any damage to the heart muscle? >> that's correct. >> let's talk about the brain. did you note any injury or

damage to his brain tissues? >> i did not. i did not notice any acute injury to his brain in the sense of physical trauma, nor in the sense of it being deprived of blood or oxygen. >> did you note anything regarding mr. floyd's lungs? >> mr. floyd's lungs were -- they had a lot of fluid and congestion. other than that they were normal. >> is it possible to get fluid on the lungs from the efforts to resuscitate mr. floyd after he was taken from the scene? >> yes. >> what kinds of fluids could cause that? >> basically what we're seeing is edema fluid.

it's a protein filled fluid that fills the lungs and the breathing spaces. we see that in people who have had protracted cpr. as their heart is not working very well, they're still getting a lot of fluid put in them. we can see that pulmonary edema from that. there's other circumstances as well. it's a fairly nonspecific finding. >> with respect to mr. floyd, you didn't or didn't need to take the time to try to understand what was the source of his pulmonary edema? >> i don't know that i could pinpoint the source with accuracy. given that he got cpr there's multiple explanations for his pulmonary edema. >> what about the prospect of what's called a pulmonary embolism? what is that? >> it's when you have a clot

form in another part of your body, most commonly the lower legs. that clot breaks off and goes straight to the lungs because that's where all the heart pumps all the blood. a massive pulmonary embolism can be instantaneous fatal. smaller pulmonary emboli can go into smaller branches of the lungs. sometimes they're asymptomatic. sometimes they can be life threatening. we look for pulmonary emboli as part of the autopsy. >> did you see any pulmonary emboli in the case of mr. george floyd? >> no, he didn't have any. >> dr. baker, let's talk about the toxicology. did you seek what's called a toxicology screen in this case? >> yes. >> would you tell the jury what is a toxicology screen.

>> so we actually use the term expanded panel because the laboratory we use, that's the terminology. in essence we send off one or more tubes of blood and some cases urine to the lab. they run a comprehensive panel looking for elicit drugs as well as scores and scores of prescription drugs. i expect you probably heard from the toxicologist. i won't go into the laboratory part of it. that's not my expertise. they test for antibodies looking for drugs like morphine and related compounds, and so on. they have the potential to detect hundreds of different of medications. that's what we call the expanded panel with the lab we work with.

that's what we ask for in most forensic autopsy. >> is the lab you work with nms? >> correct. >> how long have you worked with nms labs? >> about 13 or 14 months now. >> for the past 13 or 14 months, would that be the only lab that you would be sending out toxicology panels or screens to from the hennepin county medical office? >> yes. all our toxicology is done by nms. >> are you familiar with the toxicologist named -- >> yes, i know dan. >> he testified here just -- time flies. i don't know if it was yesterday or two days ago. he testified here.

do you have a good opinion of him as a toxicologist? >> he's been great to work with so far. >> hold on. the objection is? [ inaudible ] >> sustained. >> you know him? >> i do. >> did you examine the contents of mr. floyd's stomach? >> i did. >> what did you note regarding contents? >> counselor, can i refer to my report? >> yes, if it helps refresh your recollection. >> i dictated as part of the exam, the stomach contains 450 milliliters of dark brown fluid and food matter resembling bread. >> did you notice pills or pill

fragments in his stomach? >> i did not. >> did you do any testing of the contents of mr. floyd's stomach as part of the toxicology assessment for mr. floyd? >> i wouldn't do any testing of that. it's possible that we could send it to a lab for testing, but i did not request that. >> were you aware of whether or not mr. floyd had tested positive for covid? >> yes, i was aware of that. not at the time i did the autopsy. i became aware later. >> was that significant to you in any way? >> that he tested positive for covid? >> yes, sir. >> this was very early in the pandemic. we were still scrambling to figure out autopsy safety protocols and what we should be wearing. in that sense it was significant. in mr. floyd's specific case, the fact he had been covid seven or eight weeks before he passed

away did not factor into my cause of death. i didn't see any signs of covid at his autopsy and his lungs didn't have anything i would expect to see under the microscope. >> was he symptomatic from your view? >> i can't assess that. i didn't know mr. floyd when he was alive. to the best of my knowledge he was generally healthy. i'm unaware he was suffering from acute covid symptoms at that time. >> did you know that mr. floyd had the sickle cell trait? what can you tell us about that? >> it's carried by about 8% of americans of african heritage. what it means is that one of the genes that codes for the beta chain of hemoglobin has an abnormal substitution. if you have sickle cell trait, chances are you will go through

life and never have symptoms. that's different than sickle cell disease. that means that both of the genes have that gene substitution. then you have sickle cell disease. people with sickle cell disease can get anemia, they're subject to a variety of infections. mr. floyd didn't have that. i wouldn't have known that except that it happens that people who have sickle cell trait, when you take a biopsy of tissue and put it in formal di hide, it can cause cells to sickle. when i saw that on mr. floyd's slides, i called the hospital lab and said do you have a blood smear for mr. floyd. it turned out that had made one during cpr. i have a pathologist who specializes in blood disorder look at the slide. there was no evidence that

mr. floyd was sickling during life. i had the lack run a sickle cell kwant tags. it came back that mr. floyd had the sickle cell trait. it was a fluke that it came back in autopsy. it doesn't have anything to do with how he died. >> what about the paraganglioma? >> i don't feel it had anything to do with his death. it was an incidental tumor i found in his pelvis. i looked at it under the microscope. i have no reason to believe it had anything to do with mr. floyd's death. >> dr. baker, i want to talk about the death certificate. >> okay. >> if we could pull up exhibit

194. i would like to talk about the press release report. dr. baker, would you identify this for the record. >> what you are looking at is the final press release my office put out once i had reached my conclusion as to the cause and manner of mr. floyd's death. >> can you explain to the jury what it means to certify a death? >> to certify a death as a physician means you fill in the cause of death, manner of death. if their manner of death is other than natural, you have to fill in how the injury occurred box. death certificates are standard in the united states. most of what's on them is largely dictated by the centers of disease control. they vary a little bit in

appearance, but the core elements are the same in every jurisdiction. name, where they were born, parents' names, did they serve in the armed forces. the medical examiner's role is the cause of death, manner of death and how injury occurred. most death certificates are filled out by clinicians, your primary care doctor you see. that person fills out death certificates for patients who die of routine natural conditions. medical examiners get involved when the death is unnatural causes. we should be the only people that certify deaths that are anything other than natural. >> doctor, if we look at exhibit 193. first, would you for the record

tell us what this is? >> this looks to be a state of minnesota death certificate for mr. george floyd. the death certificates are produced by the state, not by the medical examiner. we fill in the parts we're responsible for. we push the data to the minnesota department of health. the death certificate is issued by the state. that's why it says state of minnesota on the top. the cause of death, the contributing conditions and the manner, that's what i'm responsible for. that's in the middle of your display. >> can we zoom in on that and show it to the jury. i think this is preadmitted, your honor. if we look at the cause of death, immediate underlying, other contributing conditions, this is the section you fill out? >> correct. >> if we see here under manner of death, it indicates homicide. tell us what does homicide mean

to you as a medical examiner. >> we apply the term homicide when the actions of other people were involved in the individual's death. it's one of five manners of death. accident, suicide, natural or undetermined. homicide in my world is a medical term. it's not a legal term. from a vital health and public statistic point of view it's critical medical examiners fill that in. you want to know how many people committed suicide in your state. how many people died of accidents in your state. it's a key piece of public health data. we don't use it as a legal term. >> exhibit 918 is a list of manners of death, the ones you talked about -- natural, accident, suicide, homicide

which i highlighted because it's what you found, then undetermined. would you tell us from your point of view as a medical examiner, what does natural mean? >> the person dies exclusively of natural diseases. >> an example of a natural disease might be a heart attack or a fatal arrhythmia as a prior cause of death? >> those are pretty vague terms. we're much more specific. to your point, heart disease, causing a heart attack would be a natural cause of death. a ruptured brain aneurysm would be a natural cause of death. metastatic lung cancer would be a natural cause of death. there's an infinite number of natural causes of death. >> if we look at accident, accidental cause of death, is a drug overdose an example of what could be an accidental cause of

death? >> most drug overdoses are accidental causes of death. some are suicide. we don't believe the person intended to die. we regard those as accidents. >> we know what suicide is. doctor, what does undetermined mean? >> it means despite the best efforts of law enforcement, the medical examiner, we never could pin down the circumstances under which the individual died. in any good medical examiner's office you'll have a small percentage of cases that go out undetermined. most are people that died of drug toxicity and based on the person's known history we don't have enough data to know whether it was a suicide or accident. if we don't know their intent, it's often undetermined. slightly less common you find a skeleton out in the woods. you have no idea why the person was there, how long they were

there. you don't really know what happened. a case like that might go out undetermined. it essentially means we never really figured out the circumstances. >> in mr. floyd's case you listed the immediate cause of death cardio pulmonary death complicated by sub dual neck compression. what does that mean? >> the heart and the lungs stopped. no pulse. no breathing. >> with respect to the term complicated, am i right in understanding this term means occurring in the setting of? >> yes. >> in other words, cardio pulmonary arrest occurring in the setting of law enforcement restraint and neck compression? >> correct. >> dr. baker, can you tell us

how it is physiologically that the sub dual restraint and neck compression caused mr. floyd's death? >> in my opinion what was going on with mr. floyd on the evening of may 25th, you've seen the photographs of his coronary arteries. he had severe underlying heart disease. i don't know we specifically got to it, but mr. floyd had hyper tensive heart disease. he had a heart that already needs more oxygen than a normal heart by virtue of its size and it was limited in its ability to provide more oxygen because of the narrowing of his arteries. in the context of an altercation with other people that involved physical restraint, that involves like being held to the ground, involves things like the pain you would have with your cheek being held against the

asphalt, those events cause stress hormones to pull out of your body. specifically adrenaline. it's going to ask your heart to beat faster. it's going to ask your body for more oxygen to get through the altercation. in my opinion the law enforcement restraint and the neck compression was more than more floyd could take by virtue of those heart conditions. >> dr. baker, a point of clarification. as a forensic pathologist, it's not part of what you do within the four corners of your job to try to calculate what mr. floyd's either lung volumes or oxygen reserves or that sort of thing would have been, is it? >> i think what you're getting at is what i would refer to a pulmonologist. those are things we can't measure post-mortem. in living people those are the

purview of pulmonologist. >> dr. baker, we did find from the toxicology amounts of fentanyl and methamphetamine in the results from the lab? >> that is correct. >> you didn't mention either fentanyl or methamphetamine in mr. floyd's system. you mentioned those, but you don't list either of them on the top line as causes of death. why is that? >> well, the top line of the cause of death is really what you think is the most important thing that precipitated the death. other things that you think played a role in the death, but not direct causes, get relegated to the other significant conditions part of the death certificate. the other significant conditions are things that played a role in the death, but didn't directly cause the death. for example, mr. floyd's use of fentanyl did not cause the neck restraint. his heart disease did not cause

the neck restraint. >> so, these are items that may have contributed, but not the direct cause? >> correct. >> no further questions, dr. baker. >> mr. nelson? i'm jeff bennett in for ayman mohyeldin covering ten day of testimony in the murder trial of derek chauvin. we have been hearing testimony from dr. andrew baker who performed the initial autopsy of george floyd. to talk about what we just heard

while the trial is inside bar we have dr. -- we're coming out of the side bar. we'll go back to the trial. >> we're going to take a ten-minute break. >> they're now taking a break. we'll pick up with analysis here. we have dr. benerji, she's the president of anchor forensic pathology. paul henderson is with us. he's a legal analyst. we have nbc news correspondent megan fitzgerald live in minneapolis. i would like to start with you, doctor. dr. baker said the law enforcements sub dual and restraint was more than mr. floyd's heart could take. that cuts to the heart of the case, does it not? >> yes, 100%. when they were talking about cause and manner of death as we

do in our practice, you know, he explained how he got to his cause of death. it's very descriptive, but then dr. baker really said this is why he died. >> so what should we expect the hear from the defense team when they cross examine dr. baker, do you think? >> you know, i think they're still going to stick with trying to weaken his stance, if you will, on that cause of death. why wasn't it fentanyl intoxication, methamphetamine use, hypertension as they went through the anatomic findings. you know, intoxication is the one thing that i question in the part too because usually i think that the person was having an

adverse event from that. i don't know where dr. baker will go with that. whether he'll say that, yes, the fentanyl could have contributed it or no, it didn't at all. fentanyl use versus fentanyl intoxication, i think methamphetamine use is really -- it was a low level. they established that. it didn't really contribute to his death. that's probably the only other avenue i see. >> paul henderson, your take on what we heard so far from dr. baker? >> i think this is really important and part of the bow that the prosecution is putting on their case. for the past week we were hearing the scientific analysis. now we're hearing the medical analysis, all about caution. this is what the defense needs

to focus on. they're timing when they're putting on their witnesses, especially the last witness, the medical examiner. i believe they wanted to time it to conclude their testimony at the end of the day so they can rest and have the jury contemplate all the evidence they presented so far without giving the defense time to cross examine and leave any doubt. >> paul, dr. baker is the 35th witness that the prosecution has called. is there a risk of calling too many witnesses? >> i think there always is. at some point the jury stops paying attention and it's too esoteric for them. one of the ways you can gauge that is by watching your jury to make sure they continue to be

engaged or they're taking notes or that it's actually relevant either to what your theory of the case is in terms of how george floyd died, or issues that you know that the defense is going to raise up. that's another reason to bring more witnesses just to close the door to make sure you're anticipating what defense is going to try and argue. in this case, like today, we saw the overextension of hypotheticals on both sides, but with two different results. when the d.a. was making his hypotheticals that went too far like with the george booth analogy with lincoln, that was a good point. when the defense point was making his hypotheticals that were so strained -- they were

misses that will come back to bite him in the end. in closing argument i would put up all the overreaching hypotheticals to remind the jury this was not -- this was george floyd and this is how he died, this knee from that defendant. it's been a lot of interesting things happening today. we'll see how many witnesses the defense will put in and the question is if he's going to risk it all and put chauvin on that stand. i don't think he is, but we'll see. >> megan, today we saw the jury was given physical exhibits of the autopsy photos of mr. floyd. they weren't shown on screen. we couldn't see it on tv. based on the court reporter in the room, how were the photos

received? >> reporter: these photos were presented to the jury during the testimony of dr. lindsay thomas. they were looking at scratches on mr. floyd's hands, on his face when he was pressed against the pavement there. from the jury, from the pool reporter in the courtroom, we were told the jurors were engaged. they were flipping through the photos. some were taking notes. george floyd's family is also in the courtroom. they were doing the same. what stood out is there wasn't any noticeable reaction. no furrowing of the brow. we understand the jurors were attentive during the prosecution's questioning of dr. thomas and not as attentive when the defense was cross exam. there was news out of the courtroom that one juror told

the judge she turned on the tv yesterday and saw a glimpse of court and she turned the tv off. the juror also said she received a text message from her mother-in-law saying it was a bad day. the judge thought it was minor and believed this juror was not intentionally trying to find information about the case. he didn't do anything further. didn't take any other steps further to reprimand this juror. jeff? >> paul, what do you make of that? >> i think it's pretty significant for this case in particular because judge cahill made a conscious decision not to sequester this jury. that's a big deal in a case like this because of the significance of this case and the notoriety of this case. what you run the risk of is having this information come to this jury when they're on their

phones or when they're watching tv or when they're speaking to anyone. certainly they've been admonished. this is a national case that everyone is talking about and watching and he does not want that to influence this jury. what i appreciate is how meticulous and specific and intentional he's being safeguarding against outside influences affecting the jury with the conversations, the questions and the open conversations that he's having with both advocates about the process to make sure we're not giving a chance for an appeal or jury tampering to come up from the defense or prosecution. keep in mind, we don't have that many alternatives on this jury. there's not a lot of jurors to go through if things start falling apart and we haven't even gotten to the defense's case yet. this has been an emotional case

and keep in mind, most jurors were not familiar with the tape at all. these jurors were chosen for their lack of familiarity. this has been traumatic for them already. we're all watching. whenever there's a ripple in the jury about outside information, that has to be taken seriously by advocates and the judge. this is just another sign of that. it's affirming for everyone else to know this process is going on and the judge is being meticulous about the process. >> good point. paul henderson, doctor, megan, thanks to you. you're sticking around as we wait for the trial to resume. we're watching another story closely. that's florida congressman matt gaetz. he's saying he's planning on fighting back as investigators allege he was involved in sex

trafficking. he's hired two attorneys to represent him. the team said matt has always been a fighter, a fighter for his constituents, a fighter for the country. he's going to fight back against the unfounded allegations against him. that statement comes as he's set to headline an event at one of former president trump's golf clubs and as one of his republican colleagues is calling on him to resign. joining us now is sahil gapour. republicans have been radio silent about this. where do you expect this to head next? >> reporter: we don't know the answer to that. is congressman kinzinger a

canary in the coal mine? he's been more willing to buck his party and to specifically criticize the trump wing of his party. he was the first house republican to come out in favor of impeaching the former president. at the end of the day there were only ten house republicans in total who voted in favor of impeachment. he ended up being a minority there. we don't know where republican leadership is going to come down. kevin mccarthy has said the allegations are serious. he intends to sit down and talk to him. he said a similar thing about marjorie taylor greene when there was criticism of her and let her go. the power within the republican party is still with that wing, the marjorie taylor greene wing, the matt gaetz wing, the trump wing. >> we've got now with us nbc news investigative reporter tom

winter. this was borne out of a probe into a florida tax collector named joel greenberg. we learned yesterday that he is likely going to take a plea in the case against him. where do things stand on that front? what does it mean for matt gaetz? >> reporter: a couple people have reached out to me. there was a story and some reporting that he pleaded not guilty. he had to, jeff. that's the process at this point. he was handed a superceding indictment and he had to enter a plea. you're not going to say you're guilty without the benefits of a guilty plea agreement with it. that's why today happened. as far as the discussions going forward, that's something they hope to wrap up. i would say by early may. they set a preliminary deadline of may 15th to come to a conclusion with an agreement or

a trial. that's where things stand as far as discussions. the attorney for greenberg made it very clear yesterday outside of court they're hoping to limit his criminal exposure as much as possible, the most effective way of doing that is cooperating at this stage. looks like that's the direction they're headed towards at this time. it will be interesting to see what greenberg can offer in this ongoing investigation. he's somebody that we're looking at on the screen. that's taken a lot of pictures with matt gaetz. we obtained his emails and he had a number of communications with gaetz' office. we'll keep you posted. >> thanks to both of you. let's go back to the trial.

>> mr. nelson? >> good afternoon, dr. baker. >> good afternoon, mr. nelson. >> if i may have a moment, your honor. dr. baker, thank you for being here this afternoon. just some follow-up questions. i want to break up into two different sections, one about the autopsy and then after the autopsy. okay? >> okay. >> you've testified in many cases in hennepin county? >> i have. >> dakota and scott county as well? >> not as much, but yes. >> in the process of exchanging

information, the defense receives copies of everything, reports, meeting notes, things like that? >> yes. >> have you had opportunity to review that information prior to testimony today? >> to the best of my knowledge, yes. >> you testified in a death investigation it's much more than an autopsy? >> correct. >> in fact, if you pull your file, it ends up being a few inches thick? >> we're paperless, but if you printed it out, yes. >> that's what i did and that's what it is. i guess i got to get with the times. ultimately that file contains your autopsy report? >> correct. >> the paperwork you fill out for the state of minnesota? >> yes. we don't get a copy of the death

certificate, but everything we put on there is in our file. >> you keep track of conversations with people? >> generally, yes. it's my investigators talking to family, investigator. >> you keep a log today so and so spoke with x, right? >> i don't personally do that, but my investigators do. >> it's all a part of this file, right? >> correct. >> in addition you obtain any known medical records that may factor into your analysis as well, right? >> yes. >> previous -- you received some hospital records from hcmc regarding mr. floyd, correct? >> correct. >> you don't go out and search -- perhaps you do -- try to search for every provider that he or any person may have seen, right?

>> in most cases that's correct, counselor. there wouldn't be point in us trying to get every medical record ever generated. it would only be if i thought it would help me understand the cause and manner of death. >> fair enough. i want to talk about the word complicating. how do you define the word complicating as you used it as to the cause of mr. floyd's death? >> i used the word complicating the way most physicians use the word complications. most patient know what physicians mean by complications. it means something occurred and there was something that was untoward on the heels of that. if somebody goes into the hospital for hip surgery and they develop a blood clot,

that's a complication. it's an untoward event that happened. that's how i look at it as a physician. >> it could be during an incident or as a result of an incident, right? >> we don't use the word incident, but it could be an immediate complication or a delayed complication. >> there are certain circumstances that precede those complicates, agreed? >> that's a little vague, counselor. >> in any death investigation you're trying to determine the cause and manner of death? >> correct. >> in this particular case you took into consideration the police restraint, right? >> correct. >> you also took into consideration the heart disease, correct? >> as well as the toxicology results, agreed? >> yes. >> you factored those in in your

cause -- there's the cause and manner of death and then there's the second thing that you left blank, right? then there's the contributing causes or contributing factors? >> yes. the term of art is other significant conditions is what you're getting at. >> that's something you have to do for the cdc or did you take those in consideration as contributing to mr. floyd's cause of death? >> when you put those on a death certificate as a physician, what you're saying is i think these played some role in this death. i'm unaware how the cdc would mandate what goes on there. presumably you put things are there you think are relevant. you don't list trivial stuff that didn't play a role. >> if something was significant enough you put it on, but if it's insignificant, you leave it off? >> generally, yes.

>> in your opinion both the heart disease as well as the history of hypertension and the drug -- the drugs that were in his system played a role in mr. floyd's death? >> in my opinion, yes. >> all right. now, again in terms of your autopsy report, you don't generally note negative finding, right? if something is normal, you may just say it's normal, but you're not going to take special note to say the heart is completely perfectly normal? >> that's a really long question, counselor. i think i can give you a reasonable answer. for most normal organs we have a boiler plate description what that is. if a spleen is normal, i'll give a normal description of the spleen with the weight of the spleen. demanding on the nature of the case there are pertinent

negatives, things that you think might be on the body based on the circumstances, so you specifically seek those things out. if they're not there, you document them because their lack -- the fact they're not present really means something. i don't know if that answered your question. there are somethings that are normal and we go on to the next step of the autopsy, there's some things the fact they're not there, you're going to dwell on that and document that you looked for something that wasn't there. >> in that regard, if you note something, whether it's odd or irregular or it's the negative, you take special precaution to note those things in your autopsy? >> ideally, yes. not only do you document that, but you take a picture of things that are there and you document

things that aren't there that would be expected to be there. >> it's interesting to me you made a conscious decision not to watch any videos before you performed the autopsy, correct? >> correct. >> that was to prevent bias you described? >> in general, yes. i don't want to go into an autopsy with a preconceived notion that i know what happened. that might lead you to skip certain steps or do certain things that could be relevant. full disclosure, counsel, to fully answer the question, i saw the video that the entire world saw later that day after mr. floyd's autopsy. i didn't release his body until the following morning. had i seen something on the video that triggered something else, i had a chance to act on it. i didn't want that in my mind when i physically performed his autopsy. >> understood. you received some briefing from

law enforcement to say here's generally what we know about what happened? >> it was pretty high level, but yes, i got a phone call that a man had gone unresponsive in police custody while restrained. he died at hennepin county medical center. that's what i knew. i believe i knew there was pressure applied to his neck. beyond that, that was what i knew going into the autopsy. >> so you were -- you took special -- because you learned that there was potential pressure to the neck, you took special steps to look at the neck, neck area, shoulders, et cetera, right? >> yes. >> because of that, you did this unique incision or this specific incision to lift the skin off to look under the surface so to speak? >> that's correct. >> all right. we'll come back to that in a second. you did note -- i want to focus

on the heart for a little bit. you noted that the heart was dilated? >> yes. >> what causes that? >> dilated is just fancy medical lingo for got a little bit bigger. when you blow up a balloon, it dilates. mr. floyd's heart was -- can i refer to my report? >> would it refresh your recollection? >> it would. i have described the ventricles as mildly dilated in mr. floyd's case. i would interpret that as being part and parcel of high blood pressure. that's a manifestation of the heart getting bigger and heavier as it works against the high blood pressure over a period of time. >> you took note of the size of mr. floyd's heart? >> it's actually the weight, but

yes, absolutely did take note. >> that was 540 grams? >> that is correct. >> you're familiar with the papers on the normal heart size? >> i am familiar with the paper, although the one i usually use is the kitzman paper from the mayo clinic. >> what's the maximum size? >> it's a function of your body height and weight. a larger person is going to have a bigger heart weight. mr. floyd's case, the upper limit of normal for his body length according to the reference i use is 510 grams. the upper limit of normal for body weight would be 521 grams. he was 540 grams. he's outside the upper limit of normal. on the bell-shaped distribution

for a man his size, he's on the heavy end. >> okay. all of this various standards in terms of the wait of a heart, they're peer reviewed? >> as far as i know, yes. the reference i use is from the going to assume is peer reviewed. >> right. as would be say demio and other studies? >> i'm not familiar with the other studies. i believe it was published in the american journal of forensic medicine which i know to be peer reviewed. >> okay. you would agree that the larger the heart is the more blood it needs to provide adequate oxygen nation. >> as a general rule, yes. >> what kind of things cause a person's heart to be bigger than normal? >> most common cause by far in adults in the developed world is high blood pressure.

there are far less common causes. aortic heart disease. genetic causes of an enlarged heart. typically we can tell by looking at the heart. those are much further down the list than high blood pressure which again is the number one by a long shot. >> based on the review of mr. floyd's medical records you determined that he has a history of high blood pressure. yes? >> it was helpful to learn that from the medical record. he was known to be hyper tensive. >> can you describe the narrowing of the arteries more? >> i can, counselor. if i may refer to my report again. >> sure. so as i mentioned, when i was describing the photographs earlier, he had 75% proximal and 75% mid narrowing of the left descending coronary artery.

he had 75% narrowing of the first diagonal branch of his left anterior ascending coronary and the right coronary he had 90% proximal narrowing. >> all right. what do forensic pathologists consider enough narrowing to cause a sudden death? >> we usually look to 75% greater as the -- as capable of causing sudden death. >> are you familiar with myocyte necrosis? >> yes. >> do you have to have that to cause a sudden death? >> no, you do not. >> in arrhythmia there would be no necrosis, correct? >> that's an electrical phenomenon and so i really can never diagnose an arrhythmia postmortem. we have to infer that from the

circumstances and the condition of the coronaries. >> apox yeah of the heart is the reduction of the oxygen to the heart, correct in. >> correct. >> can you -- can hypia to the heart cause death by other means or would it just be the arrhythmia? >> well, there's many ways that a lack of oxygen to the heart could cause death. one would be a sudden disrim mia from a normal beat to a nor profusing beat and the person literally collapses in front of you. depending on the nature of the disease the person should have a thrombis. there's different ways the heart manifests that it's not getting enough oxygen but one is sudden collapse and death. >> and sometimes people can

survive that for a longer period of time. >> survive -- >> the thrombis you described? >> correct. i don't know the numbers but obviously people can and do survive in the coronary arteries and why we have clot busting drugs and urgent katherizations. >> can you describe the conduction system of the heart? >> only in the broadest terms because i'm not an expert. i have other people i rely on that but it's the electrical part of the heart. there's like the little watch in your heart that starts every heart beat. you would be able to see what it is doing on an ekg looking at an electrical tracing in a living person. that's conducted to another node known as the av node. and then the impulses go from that to the ventricle that cause

them to beat. you can see it under the microscope if you take it out and look for it. and there's on very rare occasions we do that. it wouldn't have been necessary in mr. floyd's case. >> if the conduction system is impaired what happens? >> i'd have to defer to a cardiologist on that because there's so many different ways it can be impaired. sometimes benign or night need a pacemaker or a defibrillator. >> which of the arteries supplies the -- that first one, the sa node? >> the sino atrial node? >> right. >> the right branch of the coronary in my people. i didn't dissect out the branch but the main right coronary

artery was 90% narrowed. >> you're aware also of the methamphetamine found in his system? >> yes. >> does methamphetamine further constrict the ventricle and arteries? >> i don't know. i'm not an expert in the specific toxicology of methamphetamine. it is hard on the heart in the sense that it does things like drive up the heart rate and blood pressure. i don't know if it's a vaso constrictor but either way as a general rule for forensic pathology it is not good for a damaged heart, a heart with coronary artery disease. >> does the amount of or the level of the tox logical findings affect whether it's good for the heart or bad for the heart? >> i don't know that there's a scientific answer to that, counselor, because i'm not aware there's a safe level of methamphetamine. >> okay.

and especially elicit methamphetamine, right? so safe level of the street drug versus the am met feigns sometimes prescribed. >> yeah. i'm very unfamiliar with any medical use for methamphetamine but amphetamine is used. that's definitely not my area of expertise. my high level overview is all other things being equal, methamphetamine is not good with bad coronary arteries. >> and exertion also causes the heart to work harder? >> correct. >> and therefore would require more oxygen? >> correct. >> more blood has to pump through to oxygenate the heart? >> correct. >> and send it to the rest of the body. and so, in this particular case, we have mr. floyd's heart is at

least above average size. right? >> correct. >> he has a heart with narrowed coronary arteries, right? >> he does. >> there was evidence of a period of exertion prior to his being deceased? >> yes. i mean, we are outside the autopsy now obviously but clear from the videotapes that, yes, there was a period of exertion prior to him becoming unconscious. >> in terms of your investigation, you ultimately did watch the videos? >> correct. >> and including the body worn cameras of the officers? >> yes. >> and did you also -- were you also provided with other videos in terms of surveillance videos, additional bystander videos, things of that nature? >> i was. >> were you provided with investigative materials that -- what people said happened, et cetera? >> no. i did not have those. >> okay.

have you ever certified a death due to hyper tensive me cardio. >> the answer to that is yes. the term is the heart is too big because of high blood pressure. we don't typically use that term but hyper tensive cardiovascular disease but i have used that or similar terminology. >> have you ever certified a death due to art ro ske lotic disease? >> yes. >> compared to mr. floyd? >> yes. >> in terms of the injuries to mr. floyd, the abrasions and things of that nature, obviously

they appear to be fresher to you. would you agree with that? >> i want to be careful in the answer. there is not any literature to date those kinds of injuries with any precision. presumably there's contextual data to know that he didn't have the abrasions an hour before he died or whatever. could i tell you how old they are as a pathologist? no. not with any precision. >> in terms of abrasions on mr. floyd's body, they could have been from the period of time he was restrained on the ground. agreed? >> correct. >> could have been consistent with the period of time where he was taken to the ground or brought to the ground. right? >> well, that would be true as long as there's something in the environment to explain the abrasions. some would take a fairly rough surface to produce. a smooth