and the other would be the tibia, which is the shinbone. this diagram shows the shinbone, and this is this object right here. and if you remove that particular red circle i just put in, you can see that the tibia has a relatively defined front edge right over here. and you can feel it on yourself, but it is a nice ridge all the way down, which is actually quite prominent. and hard. and it's right underneath the skin. and so that allows an unforgiving surface such as the shinbone to be placed on soft tissues which are more vulnerable and cause some degree of injury to that area. so that's the shinbone. the knee is actually not that much different. the knee is near the patella and you have the ends of the femur, the thigh bone, and the ends of the tibia just below. all of which are bony prominences, and again, right underneath the skin. and they can direct the amount of force. if you put a substantial, 30, 40, 50 pounds worth of force focused with your knee onto somebody, in my opinion is the chances of a subcutaneous or intermuscular hemorrh

that is the shinbone. the knee is different. you have the end of the femur and the side down on the side and the tibia just below that are all right under the skin. they can direct to the amount of force. if you put 50 pounds worth of force with your knee on to somebody come in my opinion the chances of a subcutaneous or intermuscular hemorrhage is very high. nelson: you did not see that in this autopsy? >> it was not documented are in the photographs. nelson: in your career as a pathologist looking another strangulation type cases? >> yes. strangulation and other restraint situations where knees have been used. nelson: do you typically see marks in those cases? >> and manual strangulation come often you will see hemorrhaging into the muscles of the neck. if the knee has been used on the back often we see a bruise consistent and at times matched it to video cam footage were any is used. yes. nelson: and finger marks? >> yes. just the pressure from somebody's fingers is enough to cause muscle hemorrhage in the manual strangulatio

. >> and when we talk about the shinbone itself, there's not a lot between the skin and the shinbone,ht? >> that is true, yes. >> and it's sort of a triangular shape, right? >> yes. >> and, again, along mr. floyd's back there's no long bruise consistent with a shinbone, right? >> right. >> and there's no more circular bruise consistent with a kneecap? >> right. >> you've reviewed obviously a lot of strangulation type cases in those -- in your career? >> yes. >> strangulation with the hands. right? >> primarily manual, but also ligature. >> ligature being like a rope or a thong cord or something? >> exactly. >> and in those manual strangulation cases the pressure that's exerted in that will frequently leave bruises, fingerprint size bruises, right? >> frequently, but not always. >> and ultimately what increases the likelihood of seeing a bruise is the amount of force that's applied, right? >> you know, i don't know what all the factors are, whether it's fragility of the vessels, whether it's the length of time, whether it's the force, whether it's the location. i think there are lots o

. >> when we talk about the shinbone the shinbone itself, not a lot between? >> that is true. >> it is sort of a triangular-shaped? >> yes. >> and again, along mister floyd's back there is no longer is consistent with the shinbone, right? and no more circular bruise consistent with the kneecap? >> right. >> you have reviewed a lot of strangulation cases in your career? >> yes. >> strangulation with the hands. >> primarily manual but also ligature. >> ligature being like a phone court or something. >> exactly. >> in those manual strangulation cases pressure exerted in that will leave bruises, fingerprint size to bruises. >> frequently but not always. >> ultimately what increases the likelihood of seeing a bruise is the amount of force that is applied. >> i don't know what all the factors are, whether it is fragility of the vessel of the weather is the length of time, the force, the location. there are lots of variables. everyone bruises different we. >> yesterday depends on what medications, yesterday there was an analysis or an analogy to sitting on a church b

. >> and of course the shinbone is just below the skin, right? >> yes. >> sort of triangular in nature? >> yes. >> so is a substantial amount of force was being used by the knee or shinbone on the neck or back area, in your line of, if the force was sufficient him will expect to see bruising? >> i would expect bruising but i don't know lack of bruising exclude that. when i pivoted which is pressure to the front of the neck to the back of the neck that is not something we see medical examiners explaining regulation more asphyxiation. >> correct signing in your autopsy shows suspicion significant, find injuries to mr. floyd fact. at the outset of his body to make sure i didn't miss anything but i didn't find bruising on his back. >> did you find changes to mr. floyd bring? >> i did not but again, a person has to survive many hours before we could see those. >> you generally are familiar with hypoxia and how that occurs? >> it really depends on the nature of the asphyxia, in my world asphyxia is hanging, regulation, carbon monoxide poisoning, all di

shape.ar >> yes. >> again, along with the flights back there is no long bruise consistent with a shinbone. >> that's right. >> there's no more circular bruise consistent the kneecap? you reviewed obviously a lot of strangulationwe cases in your career? >> yeses. >> the strangulation of the hand?la >> and ligature. >> like a phone cord or something? >> exactly. >> in the manual regulation cases, the pressure exerted and that will frequently leave bruises? fingerprint size bruises? >> frequently but not always. >> ultimately, what increases the likelihood of seeing a bruce, the amount of force applied? >> i don't know what all the factors are, whether the fragility of the muscles, length of time, the location, i think there are lots of variables. >> -- everyone bruises. >> yesterday, it depends on what medications they may take. yesterday there was an analysis or analogy sitting on a church bench and you don't bruise your behind. [laughter] >> would be different if you're sitting on a church bench with a baseball for example under your but? >> i really couldn't say. >> in terms of doctor ba

floyd's back there's no long bruise consistent with a shinbone, right? >> right. >> and there's no more circular bruise consistent with the kneecap. >> right. >> you have reviewed obviously a lot of strangulation type cases in those, and your career? >> yes. >> strangulation with the hands, right? >> primarily manual but also ligature. >> ligature be like our rope or a phone quarter stomach? >> exactly. >> and in this manual strangulation cases the pressure that is exerted in that will frequently leave bruises, fingerprint size bruises, right? >> frequently not always. >> and ultimately what increases the likelihood of seeing a bruise is the amount of force that is applied, right? >> you know, i don't know what all the factors are, whether its fragility of the vessels, whether it's the length of time, whether it's the force, whether it's the location. i think there are lots of variables. >> so -- >> everyone bruises gently. >> so yesterday depends on what medications they may take. >> right. >> yesterday there was an analysis or an analogy to sitting on

. >> of course, the shinbone is just below the skin, right? >> yes. >> and it's sort of triangular in it nature, right? >> on cross section, yes. >> so if a substantial amount of force was being used by the knee or the shinbone on the neck or back area in your line of work and if that force was sufficient to asphyxiate him, would that, would you expect to see bruising? >> i would expect to see bruising but i don't know that the lack of bruising excludes that. you and i just pivoted from strangulation, which was pressure to the front of the neck to pressure at the back of the neck and that's not something i think we see as medical examiners, pressure to the back of the neck explaining a strangulation. >> or asphyxiation. >> correct. >> so is there any objective medical finding in your autopsy that shows a sufficient or significant amount of pressure to the back? >> again, i think we've covered this. i did not find any injuries to mr. floyd's back. not on the outside of his body. not looking at the soft tissue under his skin to make sure i didn'

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 na

and so if a substantial amount of force was being used by the knee or the shinbone and the neck or back area, in your line of work, and if that force was sufficient to fix it him, would that we do expect see this. >> on expect to see a bruising but i don't know that the lack of bruising excludes that. you and i kind of just pivoted from state regulation wishes pressure to the front of the neck to the pressure of the back of the neck. and that is just not something that i think we see his medical examiner's pressure to the back of the neck is a strangulation pretty. >> or an appreciation pretty. >> correct. >> so is there any objective medical in your autopsy that shows a suspicion or significant amount of pressure to the neck. >> again i think we've covered this, he did not find any injuries to mr. george floyd's back, on the outside of his body not looking for soft tissue and risking to make sure that i didn't miss anything. urit did not finding any bruises on his back. >> did you find any changes to mr. george floyd's brain pretty. >> i did not but again a person has to survive for an

taking into account how much weight, figure he carries and you have to remove out the weight of his shinbone and his boot so subtract that all and then you can calculate the weight. >> you also calculate the changes when narrowing the space people have to breathe through. >> yes, separately. >> would this be akin to breathing through a small opening like a straw? >> it would. when you breathe through a narrow passageway, it's like breathing through a drinking straw but much worse, breathing through a drinking straw is somewhat pleasant but not that unpleasant and then it gets much worse. >> as the space narrows, is it more difficult than to breathe through? >> enormously more difficult. >> to physics then is that something that can also be calculated? >> yes. >> that type of calculation, would it be specific to george floyd? >> it wouldn't, it would be for anybody, we know in terms of what happens when you have this level of narrowing, this will happen to anyone. >> can you explain to the jury what the calculations would show about the area? the airway on breathing? >> yes. i believe this ex

body weight taking into account with the gear that he carries and also remove the weight of his shinbonend his boot subtracting these and then you can calculate the weight. blackwell: can you calculate the changes or narrowing in the space people have to breathe through? >> yes. separately. blackwell: is this again through breathing through a small opening like a straw? >> if you breathe through a narrow passageway, it is like breathing through a drinking straw but it's s much worse. breathing through drinking straw is somewhat unpleasant but not that unpleasant and then it gets much worse than that. blackwell: is a space narrows is it more difficult to breathe through? back enormously more we know that through physics. blackwell: could also be calculated. >> yes. blackwell: that calculation is a specific to george floyd? >> no. anybody we know physiologically when you have that level of narrowing it would happen too anybody. blackwell: explain to the jury what those calculations would show of the effect with the airway on breathing. >> i believe there is an exhibit that relates to that