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Pathologist Testifies in Zimmerman Case.

Aired July 9, 2013 - 11:30   ET


DR. VINCENT DI MAIO, FORENSIC PATHOLOGIST: This case, again, that he was alive at the time he was shot and that the muzzle was not in contact, but had to be back.

The first time you see powder tattoo marks is when the muzzle is a half inch away. Less than half an inch, you don't see tattoo marks. And as you begin to move the barrel away, the area of tattooing begins to get bigger and bigger and bigger. And then as it increases in range, your density will decrease. This is a fairly heavy density. So you know it's, you know, less than six inches and such. And the density decreases, until, finally, the tattoo marks disappear. This is ball powder, most probably flattened ball. It would disappear from bare skin at about three feet. But by the size, the density, this is close, somewhere between two and four inches.

DON WEST, DEFENSE ATTORNEY: Your opinion as to the distance is based upon your training and research?

DI MAIO: Yeah, I've done a lot of research in powder tattooing, and whether you can make valid judgments as to range. That is, what firearms examiners will do, they'll use like, usually, heavy white paper and they'll fire the gun, and they get a whole, and then they get marks around it. And then, by the size of the pattern of the density, they'll give an opinion as to the range. Well, this has been used for 75, 80 years, to make judgments. Was the problem was, does it really reflect what happens on the skin? And I got curious about that, so I decided to make a determination, and I did experiments. And you have to use living animals to do it.

And based on the experiments, I found out that, yes, it's valid. To determine the size of a pattern by shooting against like white paper is valid, out to at least 18 inches. So I got interested in there, with and then I did determinations of powder that to go from handguns and shotguns and rifles and how far it extends and how different types of powder makes such a determination. This is a ball powder variant, so it actually, it is a lot more grains than a cartridge loaded with powder, with ball powder. So you have a denser pattern. And because of the configuration of the grains of powder, they actually go out further. And I know it's ball powder, because the firearms examiner states that in her report.

WEST: Dr. Di Maio, the exhibit you just published to the jury is now on the screen. The detail may not be as good as on the photograph itself, but that's in evidence, the jury can review later. This is what you described as the two-inch-by-two inch tattooing pattern?

DI MAIO: Yes, sir.

WEST: Is that what helps you with more precise about the distance than just the half-inch, where you said it can't be less than a half inch, or the beyond 18 inches or several feet, where you know the powder would have dropped off.

DI MAIO: Right. If it's less than half inch, you would see a hole surrounded by dense foot, and you would not see individual powder tattoo marks. Powder tattoo marks begin, in the metric system, 10 millimeters. It's about half inch. And then begin to -- you know, the powder gets broader and broader.

WEST: How does -- sorry -- how does the pattern get broader as the distance increases?

DI MAIO: It's kind of like with a hose. When you have that spray coming out. You know, the cone shape, and, you know, the farther you get from the end of the hose, the bigger the spray pattern. So it's like that. But, of course, what happens is, just like the hose, after a while, the water droplets just fall off. You can only spray so far. It's the same thing with the powder. After a certain distance, it loses its velocity and just falls away.

WEST: Would the clothing -- it's not disputed in this case that the -- there was clothing in-between the end of the muzzle and the skin. In fact, we have the shirt here in the courtroom, if it would assist in your testimony, with the jury, but the question is, what effect, if any, would the clothing being in between have on the appearance of the wound itself on the skin?

DI MAIO: In this case, none. Because the clothing was not between the powder and the skin. At the time of discharge. Because there was a hole there produced by the gas and bullet. So don't forget, the powder is behind the bullet. So the gas tear open the clothes and the bullet makes sure there's a hole there, and then the powder comes through there. Now, if you had the gun, say, six inches away from the clothing, the clothing, you'll have just a little hole, and the clothing will filter out the powder, to a degree. But in this case the filter didn't powder out the clothing, because the clothing wasn't there. You had a hole there, and you had the muzzle against the body, and so everything coming out the muzzle was going through the hole.

WEST: If the muzzle of the gun had been pressed into Trayvon Martin's chest, even with the clothing in-between, what would you see differently than what you see here?

DI MAIO: You would see a hole like that, and it would be surrounded by a halo of black soot, and maybe on the skin, a grain or two of powder. But you wouldn't see powder tattooing. Because what the clothing would do, it disperses the soot. It doesn't disperse the powder. The powder would be inside the body.

WEST: From a medical examiner's standpoint, with your training and experience, literally having written the book, is this a hard call for you?

DI MAIO: No. This is basic, you know, 101.

WEST: Let's talk for a moment, if we might, about the trajectory of the bullet itself, and having reviewed the medical examiner's report, included the photographs, I take it, that were available of the internal examination?

DI MAIO: No, there weren't photographs of the internal examination. There was an x-ray. Which is actually better. Because the bullet can shift around.

WEST: Let's talk about the -- well, reference the x-ray, if you wish. That's in evidence too, somewhere in this stack. But also that you know path of the bullet through the right ventricle and into the lower left lung.

DI MAIO: Right. Well, what the autopsy describes --


WEST: I'm sorry, the lower right lung. I'm sorry.

DI MAIO: What the autopsy describes is a bullet hole in the left chest, as I said, an inch to the left of the midline. It goes through the, what's called the fifth intercostal space. That is, in between your ribs, you have spaces. The fifth intercostal space is the space between your fifth rib and your sixth rib. So it went through there, and then it hit the sack surrounding the heart, went through the right ventricle of the heart, in and out. And then it went into the right lung. And when you look at the x-ray, you can see the lead core of the bullet in sort of the center. And then you see the jacket fragments on the right side of the chest. So the bullet really went from the deceased's front to his back, and from his left to his right, because it went into the right lung, and started out on the left side.

WEST: Meaning there must have been, based upon your review of the description of the autopsy, must have been at least a slight left-to- right trajectory?

DI MAIO: Yes. There's some. I can't really quantitate it, but there's some that the bullet was going from Mr. Martin's left to his right.

WEST: I wanted to point that out, meaning from Mr. Martin's right, toward Mr. Martin's right.

DI MAIO: That's correct. There's a standard way of describing wounds. And when you describe wounds and when you talk left to right and up and down, you're talking from the deceased's viewpoint, not from you looking at him. So whenever I would say, like, from front to back, it means Mr. Martin's front to his back, his left to his right.

WEST: In other words, it was not precisely a straight-on shot?

DI MAIO: No. It does not appear so.

WEST: Let's talk for a moment about the mechanics of that shot, putting together the defect on the clothing, that's a result of contact with the muzzle, that you believe that the distance between the clothing and skin was somewhere between two and four inches, not in contact. Your understanding of Mr. Zimmerman's statement, because of the video reenactment, your work, essentially, or your task was to determine whether the medical evidence was consistent with what Mr. Zimmerman said happened. Is that --


DI MAIO: That's fair.

WEST: Let's talk about that for a moment. First of all, were you aware that Mr. Zimmerman said that Trayvon Martin was straddling him?

DI MAIO: Yes, sir.

WEST: And leaning over him?

DI MAIO: Yes, sir.

WEST: And that Mr. Zimmerman had the gun in his right hand?

DI MAIO: Yes, sir.

WEST: And if you would, describe, then, what you know about that sequence of events, compared with the medical forensic and gunshot evidence.

DI MAIO: The medical evidence, the gunshot wound, the tattooing is consistent with his opinion, with his statement as to that. And the reason it is, is, don't forget, the simplest thing is the gun was in his right hand. So if you're going to shoot somebody and you're right-handed and you're real close to them, the -- there's the natural inclination to, with a twist of the hand, that the bullet will tend to go from the deceased's left to his right, OK? But that's a minor point. The most important point is the nature of the defect in the clothing and the powder tattooing. That is, if you lean over somebody, you would notice that the clothing tends to fall away from the chest. If, instead, you're lying on your back and somebody shoots you, the clothing is going to be against your chest. So the fact that we know the clothing was two to four inches away is consistent with somebody leaning over the person doing the shooting and that the clothing is two to four inches away from the person firing.

WEST: You may consider, in your opinion, as well, that the clothing was wet, Mr. Martin's shirt was described as being damp, that it had been raining that night, and that when it was photographed at the medical examiner's office the next day, it was obviously wet in places. You may also consider that the responding officers found an unopened can of a beverage in the front pouch of Mr. Martin's hooded sweatshirt. This is in evidence as exhibit 148, an unopened 23-ounce can of a fruit beverage.

DI MAIO: Yes, sir.

WEST: Do you find those facts consistent with what you saw, as well as consistent with what Mr. Zimmerman said happened?

DI MAIO: That would tend to reinforce, because, the reason that the clothes, as you bend force, the clothing falls away from the body is gravity. Now, if you have wet clothing, clothing is heavier. And there's going to be a greater tendency to fall. And if you have something in the front, pulling the shirt down, as you lean over, again, it tends to pull away from the body. So, the wound, itself, by the gap, by the powder tattooing, in the face of a contact with the clothing, indicates that this is consistent with Mr. Zimmerman's account, that he, that Mr. Martin was over him, leaning forward, at the time he was shot.

WEST: Let's shift gears for a moment and talk about Trayvon Martin's -- the mechanics of the effect of Trayvon Martin receiving that shot, in terms of how long you believe he would have survived and how long, within that time, you believe he may have been conscious, and further, what, if anything, he could do voluntarily during the time he was conscious. Whether he could talk or move or be physically active. You follow me?

DI MAIO: Yes. There are three questions that you've brought up. Number one is conscious -- is the able to move. That -- that is determined by the amount of oxygen in your brain. Of which you have a reserve of 10 to 15 seconds. So even if I right now reach across, put my hand through your chest, grabbed your heart and ripped it out, you could stand there and talk to me for 10 to 15 seconds, or walk over to me because the thing that's controlling your movement and ability to speak is the brain. And that has a reserve supply of 10 to 15 seconds.

Now, that's minimum. That assumes no blood is going to the brain. If you get some more blood going to the brain, that could be longer. OK? It's just going to depend on blood pressure and how severe your wound. The other thing is, and I know the answers are kind of getting complicated, not being simple is, that some people get shot and immediately collapse, some people get shot, don't even know they've been shot. So they can function. So what I'm saying is minimum is 10 to 15 seconds. That's a given, OK?

Now, how long can your heart beat, because I'm using the time of death cardiac, not brain. That's not relevant here. OK. Cardiac. In case you have a through-and-through hole of a right ventricle, and then you have at least one hole, if not two, into the right lung. So you're losing blood. And every time the heart contracts, it pumps blood out the two holes in the ventricle and at least one hole in the lung. So you're losing blood. If you engage in a struggle, which is what was supposed to have happened, your heart rate increases.

Mr. Martin was a healthy young man. If he's involved in a struggle, you expect his heart to be going, beating, especially after he gets shot, more than 100 times a minute. You know, healthy people, 120 in a struggle is no big deal. Now, remember, every time the heart beats, out comes the blood. Now, if he loses -- say it's only beating 100, which is relatively slow. If he loses 15 -- if he loses, OK, we've got the three things. Say he loses a tablespoon of blood every time the heart beats, which is, you know, you've got two big holes in the heart. So if you lose that, a tablespoon, that's not that much. That's 15 CCs. The heart is beating 100. You're losing 1,500 CCs in a minute. That's about a quarter of his blood and the second minute if he can assume the same rate, the heart will probably be beating faster. He's going to lose another 15.

That means he's lost more than 50 percent of his blood supply. Very suddenly. It's not just the loss of blood. At that point, he's not pumping any sufficient blood to the heart or brain and he's reached a point where he's going to die. Assuming these conditions and all probability, nothing's 100 percent, he's going to be dead within one to three minutes after being shot in this case. All I'm talking about his heart effectively pumping blood. You can still get some electrical activity, but you're not pumping. This is an all probability. How long was he conscious? Significantly shorter than the time necessary to die because you wouldn't have sufficient oxygen getting to the brain. I can't tell you exactly how long he could be conscious. I could tell you the minimum, 10 to 15, unless psychologically he just blacks out. That's the best you can give in essence.

WEST: In your training and experience, are you familiar with incidents where individuals received a similar or even more serious injury than you see that Trayvon Martin sustained and could still talk, move, do voluntary actions for that 1O to 15 seconds?

DI MAIO: Oh, yes. Best case I have, speaking like a forensic pathologist, an individual shot at point-blank range in the chest with a shotgun, he turn around and ran around 65, 75 feet before he collapsed.

WEST: Does the fact of being shot in the heart itself mean anything other than it has an accelerated loss of blood and will quickly deplete the oxygen to the brain because of the loss of circulating blood?

DI MAIO: Nothing else than that.

WEST: It doesn't cause the same kind of physical response as being shot in the head?

DI MAIO: Right. Some of the swat teams, if they want to immobilize somebody immediately, you have to shoot them in the head.

WEST: From what I understand you to say then for at least 10 to 15 seconds after Mr. Martin sustained the shot he would have been capable of talking and of voluntary movement?

DI MAIO: He could, right. Some people just lose consciousness immediately. It's psychological. It's not physical. He has the potential for 10 to 15 seconds minimum.

WEST: Which could include moving his arms from an out stretched position to under his body?



WEST: Could that include moving his arms from an out-reached position to underneath his body during that 10 to 15 seconds?


WEST: At the time that one loses consciousness, I take it they then lose the ability for voluntary movement?

DI MAIO: Oh, yeah. Once you're unconscious you don't have voluntary movement.

WEST: You would not be feeling pain?

DI MAIO: That's correct.

WEST: Let's talk for a moment about the injury to Trayvon Martin's knuckle. Do you remember there being in the photographs and the discussion in the autopsy an abrasion on the left hand fourth finger?

DI MAIO: Right.

WEST: Do you agree with Dr. Bao that's an abrasion-type injury?

DI MAIO: It appears to be.

WEST: Is that consistent with having come in contact with a hard surface or impacting some other surface?

DI MAIO: It's consistent with impacting a hard surface.

WEST: Would concrete qualify?

DI MAIO: Concrete can qualify, yes.

WEST: In your training and experience under circumstances like this, would you expect to see bruising on the knuckles if there had been punching going on?

DI MAIO: You can see bruising or you cannot see bruising. It depends what part of the body you punch. The softer the portion, you may not see it. In a case like this you can have bruising but it may not be visible unless you cut open the hand, the skin and peel it back. There may have been bruising there that we don't know about or there may not have been bruising but it doesn't make that much difference. You can punch someone and not get bruises and punch someone and get bruises. It's just too variable.

WEST: Does it take blood pressure in order to get bruising?

DI MAIO: Yes. Once your blood pressure goes, you can't get bruising. That's why they say you can't bruise a dead body. No blood pressure. The bruising occurs when the blood pushes the blood out of torn blood vessels into the soft tissue.

WEST: In this instance, Mr. Martin lost blood pressure quickly? DI MAIO: Yes, sir.

WEST: Had Dr. Bao been looking for bruising, especially in the knuckles, the better course or the better practice would have been to take a look internally?


WEST: As far as you know that was not done in this case?

DI MAIO: That's correct, sir.

WEST: Let's then move, if we might, to the injuries that George Zimmerman sustained. You've been provided photographs that were taken at the scene of his bloody nose, is that right?

DI MAIO: Yes, sir.

WEST: A photograph that was taken of the back of his head showing some streaming blood?

DI MAIO: Yes, sir.

WEST: Were you also provided with copies of the photographs that were taken later that night some four, four and a half hours later by the Sanford Police Department?

DI MAIO: Yes, sir.

WEST: Let's talk then a little about head trauma. Let's talk about the mechanisms or the mechanics of blood-force injury to the head.

DI MAIO: Yes, sir.

WEST: What happens when somebody is hit in the head either by a fist or has their head impacted against the hard surface like concrete?

DI MAIO: Well, OK. The -- what will happen is the brain, the head will move. The head space then all of sudden it's made to move or it's moving, hits, and stops suddenly -- it works the same way -- the brain will shift. The brain is kind of like gelatin. It will move back and forth inside the cranial cavity. As it moves back and forth, there's three possibilities. One, you get bruising by impacting the bone inside. The brain can come back and hit the bone so hard, you get bruising. Or (INAUDIBLE). You can get intracranial hemorrhage. If it's sufficient enough, it can kill you.

The other type of injury you can get to the brain is axonal injury. The brain is a mass of brain cells. They're all connected together. The connection in part is through fibers called axons that run from one cell to another cell, and it passes down certain chemicals which activate the cells. Now, the axons, as I said --