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Prosecution Questions Forensic Pathologist in Chauvin Trial; Forensic Pathologist Says, Primary Mechanism of Death is Asphyxia or Low Oxygen. Aired 11:30a-12p ET

Aired April 9, 2021 - 11:30   ET


JERRY BLACKWELL, PROSECUTING ATTORNEY: Have an opinion to a reasonable degree of medical certainty that Mr. Floyd would have died that night had he not been subject to the subdual and restraint of the police?


DR. LINDSEY CAROL THOMAS, FORENSIC PATHOLOGIST: There's no evidence to suggest that he would have died that night except for the interactions with law enforcement.

BLACKWELL: Now, were there -- were there other mechanism that you felt contributed to Mr. Floyd's death?


BLACKWELL: Could you generally characterize what those were?

THOMAS: Sure. So I think a secondary mechanism in this case is what I refer to as physiologic stress. And by that, I don't mean, like the stress, oh, somebody is a type A personality and they have a deadline at work and they're just really stressed about it.

I'm not talking about that kind of stress. I'm talking about the kind of physical stress you feel when you're driving along and all of a sudden a car swerves right in front of you and you slam on the brakes and you realize, oh, my gosh, if it that -- if I hadn't react, if that had happened a second earlier, I would have been in a potentially fatal car crash.

And you can feel your heart race and you kind of -- and then the car speeds on and you slow down and you realize, I'm okay, everybody in the car is okay. And, you know, your heart rate slows and -- or I think even worse, you're at the beach and you suddenly realize my toddler, I haven't seen my toddler in -- oh, my gosh, where is my toddler and that -- just that rush of adrenaline you get and you feel flushed and you get goosebumps and your heart races and feel short of breath and then there they are, they're getting ice cream cone and you go, okay.

But it takes you a minute for your heart to kind of slow down and your blood pressure to slow down and you need to be able to breathe and recover yourself. So that's the kind of physiologic stress I'm talking about, only instead of after a second or a minute, this goes on for minute after minute after minute after minute for nine minutes, where you are terrified and you can't -- there's no recovery. So it's that kind of fear of life that I'm talking about for physiologic stress.

BLACKWELL: Are you able to tell us what is going on in the body during the physiologic stress?

THOMAS: So it's -- the reactions are you get chemical release, you get adrenaline, more adrenaline, or epinephrine, more epinephrine, and those are things that make your heart race, your blood pressure, you require more -- your muscles get ready to act, to go run, to do whatever you need to do, slam on the brakes, and so you start needing more oxygen in your muscles. You need to take more breaths. You need more oxygen for your heart rate because your heart is beating faster.

There may be other chemicals that are released, whether it's, you know, stress hormones or cortizol or things like that. There may be lactic acid that's produced as your muscles -- when you have a heavy workout, your muscles get tired and kind of sore, it's because there's been an increase of lactic acid and it's your muscles working.

So all of those physical things, those chemical things, can cause reactions in the body that put additional stress primarily on your heart, but also on all of your body systems because your body requires your chemistry to be in very fine balance. And when there is too much, say, lactic acid, or too much -- not enough, you know -- not an ability to compensate for that elevated lactic acid, then all of your body organs will get into trouble.

BLACKWELL: Doctor, do you consider that physiological stress that you're describing a direct cause or mechanism of death or is it secondary?

THOMAS: Well, it -- I guess I would consider it a contributory cause -- or contributory to the cause of death. It's another contributing mechanism.

BLACKWELL: And so the direct cause is what and then the secondary cause is what?

THOMAS: So there is sort of primary mechanism, I think, is asphyxia and the secondary -- or low oxygen and the secondary mechanism is this physiologic stress.


But, ultimately, the cause of death is the subdual, restraint and compression.

BLACKWELL: So this physiologic stress or physiological stress that we're discussing, is that something that can be observed on autopsy?


BLACKWELL: And why is that?

THOMAS: Well, it's a chemical reaction. It's increased heart rate, which, of course, we don't see at autopsy. It's increased chemicals that we don't -- can't test for at autopsy. So none of it is anything that can be seen physically.

BLACKWELL: So it's a functional mechanism?

THOMAS: Yes. Yes, that's a good way of describing it.

BLACKWELL: Is low oxygen then also a functional mechanism?


BLACKWELL: So, could you tell us how you felt the physiological stress was significant to your conclusion on the cause of Mr. Floyd's death?

THOMAS: So, Mr. Floyd was already in a position where he was experiencing difficulty breathing and getting enough oxygen in his body. And on top of that now, there's this physiologic stress that is putting increased demand on his heart, increased demand on his lungs, increased demand on his muscles.

So all of the things that he is using, his muscles, his strength, his body to try and get himself into a safe position where he can breathe, those are being doubly stressed by the position that he's in as well as the underlying chemical reactions that are going on in his body. So it's kind of a double-whammy to his heart and lungs and muscles and his whole system.

BLACKWELL: So, Dr. Thomas, I want to show you Exhibit 194. Again, your honor, it is stipulated to subject to foundation later.

First, Dr. Thomas, can you tell us what this is?

THOMAS: This is a press release that was put out by the Hennepin County Medical Examiner's Office at the time they certified the cause and manner of death of Mr. Floyd.

BLACKWELL: And is it your understanding that the medical examiner's office generates this type of a press release report in certain cases?


BLACKWELL: So there's a section in the press release report that refers to manner of death?


BLACKWELL: Let's see if we can highlight that. And we see the word there, homicide.


BLACKWELL: We saw -- we see also in here information we saw on the death certificate with a press release says also how the injury occurred.


BLACKWELL: And would you read that for the record?

THOMAS: How injury occurred, decedent experienced a cardiopulmonary arrest while being restrained by law enforcement officers.

BLACKWELL: Again, you agree with that?


BLACKWELL: So, let me show you what is marked as Exhibit 918. And homicide is a manner death?


BLACKWELL: And would you explain to the jurors a little bit about what it is medical examiners look to when they're trying to determine manner of death?

THOMAS: Sure. So, unlike cause of death, which could be anything, we only have five options for manner of death. So a death can be natural, meaning that all of the conditions that contribute to the death are due to just innate processes. It could be cancer, it could heart disease, something like that.

Second category is an accident, and that would be something like a motor vehicle crash or an unintended drug overdose.

Third category is a suicide, which is death at once own hands, with at least probably some element of intent.

The fourth category is homicide, and that means death at the hands of another.

And then the fifth category is undetermined, and that means, generally, we don't have enough information about this type of death to make a determination to fit into one of the other categories.

So, for example, we talked a lot about terminal events early on.


and in some cases, we have no idea what the terminal events were because the person is just found dead their residence. And we don't know because they have been (INAUDIBLE) from family. We don't know were they saying they were going to take their lives, do they have prolonged history of using drugs, did they just get out of prison. We're unable to get enough information to sort it into was this an accidental death or was this an intentional suicide death.

And so that would be an example where we might use undetermined, where we just don't have enough information.

BLACKWELL: So, Dr. Thomas, looking at the screen in front of you, does this depict or show the manners of death?

THOMAS: Exactly.

BLACKWELL: And homicide is highlighted reflecting what Dr. Baker found?


BLACKWELL: And do you agree with that finding?


BLACKWELL: In the case of George Floyd?

Your honor, we offer Exhibit 918.


In the exhibit, (INAUDIBLE) without the highlight, is that correct?

BLACKWELL: Yes, your honor. Yes.

CAHILL: 918 is received.

BLACKWELL: For the ladies and gentlemen of the jury, these are the five manners of death that you were describing, Dr. Thomas?


BLACKWELL: And we've highlighted homicide to reflect what Dr. Baker found and that you agree with?


BLACKWELL: Is there any guidance given to medical examiners about how to select homicide as a manner of death?

THOMAS: Yes. There is a guide that was published by the National Association of Medical Examiners that provides assistance in how to make a determination between these different manners.

BLACKWELL: I want to show you what's been marked as Exhibit 952. Do you see that, Dr. Thomas?

THOMAS: Yes. Yes.

BLACKWELL: And is this the publication that provides the guidance to medical examiners on how to determine the manner of death?


BLACKWELL: With reference to excerpts of this guide be helpful to your testimony?


BLACKWELL: Your honor, we offer excerpts from Exhibit 952.

CAHILL: Any objection?

UNIDENTIFIED MALE: Yes, I do object to this, your honor. (INAUDIBLE) sidebar?

CAHILL: Actually, this is a good time to break so we can deal with the sidebar issue as well. Members of the jury, we'll take our 20- minute -- we're probably going to have some work here. So let's come back around five after, 11:05.

KATE BOLDUAN, CNN NEWSROOM: All right. Hello, everyone. I'm Kate Bolduan. As you just head from the judge there on the courtroom, they're going to take a brief break. They're in the midst of this witness testimony of a forensic pathologist in the murder trial of Derek Chauvin.

Let me bring in former Federal Prosecutor Laura Coates, as well as Chief Charles Ramsey for some more on this.

Laura, they went for an extended period of time so far without taking any breaks or even any sidebars with this forensic pathologist testimony. Give me reaction to what we've been hearing.

LAURA COATES, CNN SENIOR LEGAL ANALYST: Well, we're hearing from this person whose job it is to investigate deaths that happen suddenly or violently to be able to determine the cause of death. This is all setting up the eventual autopsy report that was drafted and created by the medical examiner of Hennepin County in Minneapolis.

And so this lays additional foundation for another person in addition to that very captivating pulmonologist yesterday, Kate, to now describe what she now believes is the manner of death.

There is an interesting point here where she talks about it that normally she wouldn't have the benefit of being able to see the events that led up to what she calls the terminal event, the idea of the moment of death. And they have to use a process of elimination in many ways to try to conclude what actually happened.

Now, the scope of the video, the different vantage points, allowed her to figure out what the steps were that led to the death and also use her training for elimination of underlying medical conditions. And she found and believes and concurs with the autopsy report that it was homicide, death at the hands of another, caused by the actions of the police officers. This is very damning testimony.

BOLDUAN: The doctors were even saying earlier on, Chief, that one thing that is unique about this case is the volume of material that she had to review. She's never -- she said she's never seen such thorough documentation of the terminal events, essentially the events that led up to the moment of death of someone that she had been reviewing their case.


Your perspective?

CHARLES RAMSEY, CNN LAW ENFORCEMENT ANALYST: Well, I mean, with video now, that's going to be more and more common. You have body camera video. You've got video from businesses, cell phones, people filming, that certainly adds to the volume of information and documents that you have to review.

But it does provide a much clearer picture of what actually took place, which is good. In my opinion, good for both the defendant as well as the prosecution, because what you want is a clear and accurate picture of what took place. You want to re-create the events that led up to the -- in this case, to the death of Mr. Floyd. And so all that is really positive.

One part of her testimony when she talked about the marks around the wrist and so forth, again, that's very consistent with what Dr. Tobin was saying yesterday about the manipulation of handcuffs. Apparently, they didn't double-locked the handcuffs. The handcuffs are on like a ratchet. The purpose of double-locking is to keep that from moving, because if it tightens, that causes pain, it causes injury. And that's what that movement of the handcuffs by the officers yesterday, that's exactly what they were doing yesterday.

So it's compelling testimony and I think it's very consistent with what we heard yesterday.

BOLDUAN: And, Laura, on the images that people in the courtroom saw, the jury, the judge had them hand out packets of these autopsy photos, not publishing them so the public us, that we could see, which is inconsistent, which is different from every other piece of evidence, every other exhibit in the case so far. What do you think of that?

COATES: Well, frankly, seeing an autopsy photo for people who are even seasoned prosecutors or police officers is very difficult to see an actual dead body. The images are seared in your brain, particularly because the way that the body contorts or how rigor mortis can set in can be extremely difficult for the average person to even witness.

And so probably out of respect for the general population of people viewing this shows you as well if the viewing public could already see this man die, imagine what the photographs must have looked like to say for the judge, look, let's not have these be shown, let's put them away.

But also one of the points that she used the autopsy for -- photos for was to walk us through and corroborate the testimony of the pulmonologist yesterday, Dr. Tobin, who talked about using one's finger, using George Floyd's knuckles, his shoulder, part of his face to try to hoist himself up to breathe all, of course, in vain. She pointed out with these photos the evidence to suggest that there was scraping, bruising, injury consistent with what he already testified about to yesterday. So this is a lot of corroboration in a way that allows the jurors to hone in at a microscopic detail level precisely what happened to George Floyd.

BOLDUAN: Laura, real quick on that, is this a consideration that the prosecution has in the case of how much graphic imagery because of the impact it has on anyone, what that -- what impact that has on a jury?

COATES: Well, prosecutors will consider it. They're not going to shy away from the graphic images they're trying to solve a -- trying to actually prove a murder case. And murder in and of itself comes with a certain element of gore.

At the same time, however, they're conscious of the fact that this is really historic to have a televised courtroom event in Minnesota. The history of it -- it's not happened before. It's unprecedented, trying to have a nice balance of things. The second time this happened, of course, in the trial, the first time being, look, we got minor witnesses, minor, according to their age, not in terms of their weight of testimony. And they had sort of the splitting of the baby there to say, we'll hear you, we can't see you.

This is similar. The jury, the people who actually need to decide this case will see it. And the witness will talk about it for the general audience.

BOLDUAN: This -- Chief, this was not a sudden death, this forensic pathologist says. This is not consistent with what she saw, not consistent at all with fentanyl overdose-type of death. And she said there is no evidence that he would -- George Floyd would have died that night except for the interactions with law enforcement. She's very clear on that.

RAMSEY: She is very clear on it. And, again, it's consistent with Dr. Tobin yesterday who actually he was able to show the exact moment in time where Mr. Floyd actually passed away, and so, again, the defense, how they counter that is going to be very interesting to see how they approach it.

One comment on the crime scene photos or autopsy photos, I've seen hundreds, if not, thousands of them. I used to work in violent crimes in Chicago, which includes homicide. It's not a pleasant thing to look at. There was no need for them to publish those publicly.


The jury saw it. People in the courtroom saw them.

But I do think that you do have to, you know, make those kinds of decisions. I agree wholeheartedly with the prosecution or the court, whoever made the decision, not to publish it publicly, because it is not a pleasant thing. And family also, they're watching this on television too. Would you really want to see your loved one like that? I don't think so. It would be very difficult.

BOLDUAN: Do you know that there's been a member -- members in kind of a rotating basis of George Floyd's that have been in the courtroom every day?

I'm curious, Laura, as well, Chief, what you think of the choice by the prosecution. Is it unusual that the medical examiner who performed the autopsy is not the first medical examiner, if you will, forensic pathologist, to be testifying here? The choice of having Dr. Lindsey Thomas, who formerly was with the same Hennepin County Medical Examiner's Office, but is now essentially in semi-retirement, speaking before they get to Dr. Andrew Baker?

COATES: You know, I think, in part, it may be out of a concern from the way that this trial was sort of hyped, the idea there might be a decision or a battle of the experts. Remember, the George Floyd family also had their own autopsy performed, which planted some seeds in the mind of the public and potentially the jury pool that there was something wrong with this medical report, this autopsy report, raised eyebrows and questions.

They probably were trying to ensure that they laid out the foundation to introduce and say, listen, this might not be the dueling competition people have made it out to be and, in fact, I want to give greater context to the medical examiner so that by the time this person explains the autopsy report, the jury has had not one but two bites of the apple to understand a lot of medical terminology.

For example, before the trial, people probably thought, okay, cardiac arrest means a heart attack, the sort of stereotypical grabbing one's chest or talking about the arm or jaw pain. They're actually able to decipher and say now, okay, they're talking about cardiopulmonary, what does that mean? That's a stopping of the heart and the lungs now.

So now, the jurors, by the time they hear from the person who actually wrote the report, are at least as informed as prosecutors want them to be on this issue.

BOLDUAN: And directly to that point, Chief, getting the -- Dr. Thomas to describe what other contributing conditions means, I thought, seems quite significant. Because not only we should -- the jury should understand what exactly that means on a death certificate and an autopsy report, but also because this is what the defense team has been pushing so hard on, the fact that there was presence or drugs in his system at the time. And that's why they've been leaning on the potential that it was a drug overdose or it was underlying health conditions that was how and why he died, not the knee on the neck in the back.

RAMSEY: Yes, they're taking away a lot of ammunition from the defense by presenting this, and getting that information out first so it can't be then used to counter what testimony that the jurors may have heard earlier.

I think Mr. Blackwell has done a tremendous job in moving through what is very complicated to really understand from these, you know, medical doctors. But he's done it in a way where he's asking the right questions, and he's asking them in a way that will elicit a response that is understandable in bite size chunks so you don't have to try to absorb it all at once. He's kind building and building and building.

He's really, really doing a good job, as he did yesterday, and, again, he follows up today with an equally impressive job.

BOLDUAN: Chief, we're wrapping up week two, and likely very possibly even today wrapping up the prosecution, laying out its case. I'd like to get both of you, but, first, to you, chief, what do you think the most significant thing is that you have learned in the course of the prosecution laying out its case here?

RAMSEY: Well, I mean, I think that the way in which they've laid it out, I mean, starting with the department, starting with the, you know, 911 operator, the trainers, with all those people, and then, of course, the chief. You know, this is not within policy. It's not part of our training. What he did was just not consistent with any kind of training he may have received. Then they kind of go into the technical aspects. So they are building, building, building and all of it builds on the previous testimony.

And I think it just makes it even that more powerful, the sequencing of witnesses. I think it was very impressive. And I've learned a lot, but I also see opportunities, listening especially yesterday to Dr. Tobin, opportunities to improve training of police officers. That's not to say he got inadequate training. So, please, don't misunderstand that, the training he received was good and was enough for him to know what he did was wrong.


But you have to always improve by having officers really understand that, you know, what is it that really happens to an individual who's in that particular position and why it's so critically important that you don't leave them in a particular vulnerable position for too long.

BOLDUAN: Laura, bring me home on this. What is your question now, when the medical examiner eventually takes the stand?

COATES: I mean, look, in a world where we can't seem to have consensus on anything, Kate, every witness agrees on the same thing and on reasonable amount of deadly force and that this was a substantial causal factor in his death.

The medical examiner for the prosecution to be successful here has got to drive home the point that when he said, cardiac arrest and excluded the phrase, asphyxia, and did not use that, he did not mean that was the cause, he was just being medically precise.

BOLDUAN: Thank you both so much. We're going to head back to Minneapolis in just a second. They're on a quick break. We're going to take you back to the murder trial as it continues of former Officer Derek Chauvin. We'll be right back.