help make a hospital come to you, instead of you going to it. so when it comes to your business, you know we'll stop at nothing. so as we come on the air right now, the judge in minneapolis is coming into the courtroom to begin today's proceedings in the murder trial of former police officer derek chauvin. medical experts expected to take the stand a day after the court erupted in a war over words. just what was george floyd saying to police about drugs in a body cam clip played before the jury? that answer could be critical to the prosecution and defense. we are live at the courthouse. we are live at the white house, where next hour, president biden

is set to go it alone on guns for now, ready to roll out executive actions meant to curb violence in this country. after those mass shootings in georgia and colorado in the last month or so. what restrictions and weapons the president is focusing on. and the fight ahead with republicans in congress already pushing back. we are joined by a top biden adviser on where this all goes from here. i'm hallie jackson in washington on this thursday morning. let's start with nbc news white house correspondent monica alba. let's look ahead in the rose garden, what specifically is president biden going to be laying out? >> the president is unveiling six executive actions, halle. these are all done unilaterally. even though candidate biden has promised to do more on what he called common sense gun control legislation. that's currently not an option. there doesn't seem to be a path forward on capitol hill. so instead in the wake of those shootings that we saw not just in georgia and colorado and in california over the last month

or so, the president is unveiling these specific actions, most of which are in coordination with the department of justice, specifically, he's going to ask the doj to issue a rule on what is known as ghost guns. these are weapons that aren't traceable or subject to background checks. they're going to be looking into action on stabilizing braces. in addition to publishing red flag legislation that can be a guide for other states to follow. and a report on firearms trafficking. the reason all of this is being done by the president and the white house now, they say, is because, again, they're not quite sure when there could be time to have action for any realistic legislation to pass. there were those bills that passed the house. but they're currently stalled in the senate so that's why you will see attorney general merrick garland in the rose garden alongside the president and the vice president to talk about what can be done from this other perspective. it's notable, halle, also the president is going to be announcing who he wants to nominate to lead the bureau of

alcohol, tobacco and firearms. that's david shipman, someone that needs to be confirmed in the senate. and there hasn't been anybody in that permanent position for more than six years. we talked a little at the top about what candidate joe biden wanted to do and really he has made some promises before the coronavirus pandemic became as large as it was about what he thought he was going to do on day one of his presidency, if elected. take a look at what the promise was on the company trail last year. >> my first day of office, i will send a bill over to congress repealing the liability protection for gun manufacturers, closing the background check loopholes and waiting period. >> reporter: so that's not something that the president was able to do. again, he said he wanted to focus his first few months in office on covid relief and getting that across the finish line, but now we are getting closer to his first 100 days as president, he wanted to do more

common sense gun control actions and has to take these unilateral steps, because there doesn't seem to be a lot of hope on the hill. the president was asked in his news conference and he said it's about timing and priority. for him right now, that appears to be the infrastructure plan. >> monica, thank you. our next guest, white house director kate bedingfield is joining us live i believe from the white house north lawn. good morning to you. >> hi, how are you? >> i'm good, thank you. let me pick up where my colleague just left off. the idea that president bind said recently that it is a matter of timing as to when he passes and looks at gun safety measures when congress gets to him. is that an exclusive acknowledgement the white house now considers infrastructure and, in fact, that's what he is putting his political capital behind? >> new york i don't think it's a question of what is more urgent. i think it's a question of how you do many things all at once.

today he is making announcements about executive actions he can take within his priority as president that will have a real impact on making sure our communities are safer and we are working to prevent these senseless gun deaths moving forward. he is somebody throughout his career in public service incredibly focused on gun reform. he worked to pass the brady bill and the assault weapons ban. this is something he feels incredibly powerful about. the actions he is announces today are the first step. he would be the first to say it's not enough. he believes congress should move on the bipartisan background check bills in front of them. so there is a lot more that we need to do. but what he the announcing today is a good first step. >> president biden as a candidate said on day one he pledged he would send a bill on gun reform over to congress. that didn't happen. you now have what you are describing the a first step of this slew of executive orders

not legislative action. is the legislative push, is there any political capital for the white house now legislatively to pass something or is the message to you, hey, congress, this is senator chris murphy's problem now? >> oh, president biden will certainly spend political capital on this. this is fundamental to our ability to keep our kids and our families safe in communities all across the country. so this is absolutely a priority for him. he still supports all of the things that he talked about on the campaign trail and wants to work with congress to move them forward. and congress could move forward on a bill to end the liability loophole for gun manufacturers as soon as they wanted to. so he wants to work with congress to move forward on this. and this is absolutely something he will spend political capital on. he believes it's incredibly important. >> the president has also announced dave shipman as etf director. so simple question on this, how confident are you that you have

the 51 votes needed or 50, of course, with the vice president breaking a tie for senate confirmation? >> well, david schiffman is an excellent candidate for this position. he has worked with the atf for 25 years. he's involved in major investigations in this country, including the oklahoma city bombing. he's a gun owner, himself. he's somebody that, you know, people from both sides of the aisle, i think, should take a look at and be able to say, this is the kind of person that we need running this critically important agency. so we're very hopeful. he will be able to get support. we believe she a qualified candidate and will be an excellent leader at atf. >> hopeful, of course, he will get support is different from confidence he will end up having that support. i wonder what conversations the white house has had, for example, senator schumer and is there a backup plan in case it runs into a buzz saw? >> this is the nominee we believe should be concerned. there is not a backup plan.

we will work to get david shipman confirmed. we believe he should. and it's something we will work on. >> let me ask you about somebody else who will be important, as you well know, to the priorities president biden has. that's senator manchin. he's out with an op-ed, he is suggesting he'd be opposed to using the budget reconciliation process, the process that will allow certain pieces of legislation to get through, perhaps more easily for democrats. under no circumstance, he says, when he votes to weaken the filibuster. the white house, i am old enough to remember a month ago, they called him a key partner. this morning you have them calling him a blow and a threat to the agenda you are working in the past? is he a blow or a threat to president biden's agenda? >> absolutely not. this is a key partner. this is how the process works. senators come forward. they'll raise their concerns, their issues. president biden wants this to be

a collaborative process. he said as much. he wants democrats and republicans to come to the table, to put their concerns on the table. i mean, what the president has said is that the only thing he find unacceptable here is inaction. so he knows this is going to be a process where there are going to be compromise. there is going to be negotiation. you know, senator manchin remains a key partner. we are doing outreach to members on both sides of the aisle in both side of the congress. because we want to work together to get these investments done. these are investments that are going to create jobs that are going to create better jobs, that are going to repair crumbling infrastructure in this country, that are going to strengthen the broadband network in this country so these are critically important investments. we want to work with members on both sides of the aisle. president biden is fully committed to doing that. >> you are caulk u talking about the importance of collaboration here. the importance of listening to people like senator manchin, who as you well snow a opposed to

that tax rate currently incorporated into the biden agenda. reading into the lines, it sounds like, perhaps, the white house is willing to compromise down to a lower rate s. that fair to say? >> i think that's fair to say. look, senator manchin said he's for a 25% increase. >> 25%? >> that means he is interested in the conduct and that means that there is room for us to work together. senator biden said he is opened to a compromise on this. that 35% was too high a tax. he said as much. 21% is too low. he wants to wind up in the middle. he is open to negotiation that allows us to sign a bill, where corporations in this country are, once again, paying their fair share and we're there paying taxes the way that working people all across this country pay taxes. so for him, it's a question of fairness. he is absolutely opened to negotiation to insure we get to a place where companies are paying their fair share and we

can afford to make these investments. >> i want to move on quickly to immigration, but very quickly. when did the president last talk with senator manchin? >> i don't feel details, rest assured, there is constant dialogue between the white house and senator manchin's office and between officers on both sides of the aisle in both houses. >> let me shift to the border here. texas governor greg abbott is calling on them to close the facility migrant team after they received a few reports on alleging neglect and abuse. hhs said in a statement that it could not comment on specific cases. here's what the governor said. >> the biden administration is now presiding over the abuse of children. the biden administration must immediately shut down this facility. >> your response to the governor, kate. and is shutting down the

facility pending an investigation something the administration would consider? >> well, you know, i think i would point you to the hhs statement, which you know makes clear, look, as the administration, we, of course, take very seriously the well-being of any children in the administration custody and that is something is that we are taking very seriously. we are investigating. at this time we do not see justification to close the facility as the governor is suggesting, but hhs is investigating and we take these claims seriously and we're going to work, hhs is going to work, i should say to get to the bottom of these allegations and at the end of the day, our focus is on making sure that these children are well taken care of and the administration will do everything it can to ensure that is the case. >> we know the president, of course, wants the vice president to lead diplomatic efforts to countries, mexico, republicans have been using that to paint kamala harris as the face of

what they call a border crisis, describing her repeatedly as the so-called crisis manager, in their view, she has come under intense criticism for not traveling to the border. did the white house believe vice president horizon vulnerable to criticism by not making her role more clear? >> no look, she has been given an incredibly important portfolio of diplomatic work in the region. it's a portfolio that president bind, himself, had when he was vice president under president obama. it's critically important diplomatic work. she will play a very important part in our relationship, the country's relationship with the countries in the northern triangle. this is diplomatic who, that will ultimately across the long term work to address some of the migration issues that we are seeing. but it's not -- it is not an assignment to quote/unquote handle the border or to be a crisis, to be a point on a crisis. what she's doing is high-level

diplomatic work is that incredibly important to our economic stability in the hemisphere. >> kate bedingfield, that is all the time we have. more questions for you. so please come back. we'd like to chat with you further. >> any time. we want to go live to minneapolis where the testimony is about to begin in the former police officer derek chauvin. it is a story we have been covering. gabe gutierrez is outside the courthouse. gabe, talk us through what we are expecting to see today, over a showdown yesterday of what was heard about a police body cam. what the audio showed there. >> reporter: yeah, yesterday, we saw some of the most aggressive cross examination from the defense so far trying to make that case that floyd died due to drug use. i want to take you to what's happening right now. testimony is yet to resume as we still see that full video with that seal. that means the court is not back in session just yet. but we are likely to see medical

witnesses, really, for the first time today. the prosecution said in the opening statement there will be a medical side to this trial. that likely might mean perhaps a pulmonologist or cardiologist to really get at the question of exactly how george floyd died. in essence, the most memorable question, most memorable words from this entire case has been "i can't breathe." today, we will probably hear some testimony to get that. of course, the defence is making the argument that floyd died due to drug use and underlying health conditions. so they will likely have very pointed cross examination questions for the witnesses today. i do want to take you, what erupted yesterday in court. and the exchange with a state investigator, who is investigating the police. he was played a short clip from body camera video and then played a longer clip by the prosecution and both sides had dramatically different

interpretations of what was heard on that video. take a listen. >> aha -- >> did you hear that? >> yes, i did. >> did it appear that mr. floyd said i ate too many drugs? >> yes, he did. >> are you able to tell what mr. floyd is saying there? >> yes, i believe mr. floyd is saying i ain't do no drugs. >> that's a little different than when you saw a portion of what occurred? >> yes, sir. >> reporter: so again, the defense trying to argue i ate too many drugs the pros sugs saying the opposite, i ain't do no drugs. certainly, that's a point of contention that will play out. again the floyd family calls it a distraction, this character assassination. today we are expecting to hear more from those medical witnesses. >> gabe, live from minneapolis, we will come back to that courtroom once testimony begins.

we expect that to happen in the next couple of minutes. but in the meantime, we will have much more coming up here on the show, including more on the latest as it relates to congressman matt gaetz, our new nbc news reporting, why a bahamas trip may be in focus. but despite one in four americans vaccinated, the cdc warning of a variant spread. we have it all after the break. k alright, guys, no insurance talk on beach day. -i'm down. -yes, please. [ chuckles ] don't get me wrong, i love my rv, but insuring it is such a hassle. same with my boat. the insurance bills are through the roof. -[ sighs ] -be cool. i wish i could group my insurance stuff. -[ coughs ] bundle. -the house, the car, the rv. like a cluster. an insurance cluster. -woosah. -[ chuckles ] -i doubt that exists. -it's a bundle! it's a bundle, and it saves you money! hi. i'm flo from progressive, and i couldn't help but overhear... super fun beach day, everybody. fine, no one leaves the table until your finished.

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prosecutors in minneapolis have just announced they plan to call the hennepin county medical examiner to the stand tomorrow. but today's testimony is continuing with dr. martin tobin, he's on the air now, a critical care specialist. we will listen to his testimony. >> you specialize if pulmonology? >> i specialize in poll monology and in critical care medicine. >> would you tell the jury what pulmonology is? >> pulmonology is the study of the lungs. it deals with all diseases that affect the respiratory system. so the lungs, the chest wall. >> so what are the various elements components of the respiratory system. >> the respiratory system begins

in the nose and the mouth and out through the wind pipe and bronchial tubes and down at the bottom to the air sacks. these are the small grape-like structures at the bottom where all the gas exchange takes place, where oxygen gets in and carbon dioxide is removed. >> so this is the system for getting oxygen into the body? >> correct. that is the prime purpose for getting oxygen in. >> now at the hospital, do you work in an intensive care unit? >> yes, i work in the medical intensive care unit. >> and that's considered critical care? >> same as critical care. these words all have the same meaning. >> is critical care different from emergency medicine? >> yes, it's very different than emergency medicine. emergency medicine is kind of the front door of the hospital. that is a triage area where you separate out where people need

to go, whereas the critical care is where you take the very sickest people. >> what kind of patients do you see in the icu? >> in the icu probably more than half of them are patients who are requiring mechanical ventilation so they're on a respirator. it may make up lungs and remaining patients will have drug overdoses, alcohol withdrawals, diabetic coma, sepsis, things like that. >> do you only see the patients in need of respiratory care in. >> no, once they come into the icu, they are patients. i am the primary care physician for everybody that comes into the icu. >> and how long have you been a physician, sir? >> i have been a physician for

three months short of 46 years, over 45 years. >> and where did you go to school? >> i went to medical school in dublin, ireland, and i took my degree there. >> not that anybody noticed the accent, but are you from dublin? >> no, i'm not from dublin. i'm from a small village in rural ireland. >> what degrees do you hold? >> i'm sorry? >> what degrees? >> the degree i hold is the mb degree which is the irish equivalent of the american md and then subsequently, i've got an m.d. through research. >> are you currently licensed? >> yes, i am licensed in the state of illinois. in the past, i was licensed in ireland and england and a number of u.s. states, but i've let them all lapse because the only place i am practicing is in illinois.

>> are you board certified? >> yes, i am board certified in internal medicine, pulmonary medicine and critical care medicine. >> so you still are accurately caring for patients? >> yes, i was taking care of patients in the icu last week and on monday i go straight back into the icu again. >> how long have you held position at loyola university school of medicine? >> i have been at loyola and hines for 32 years almost. >> before going to loyola, were you practicing medicine somewhere else? >> yes. i spent seven years at the university of texas at houston are. >> did you also set up a sleep clinic in houston? >> yes, i did. and that would have been in the early '80s, so i set up one of the very first sleep labs in the united states for evaluating patients with obstructive sleep

apnea? >> so how do sleep disorders fit within your expertise? >> because this is related again to breathing and the problems with sleep, particularly people who senator and the people who senator during thetime nighttime, they occlude their upper airway and they can hopefully stop breathing, 500, 600 times a night and during that time the level of oxygen in their blood will go very low and the basic problem in sleep apnea is because the soft palate, meaning the roof of your mouth is your hard palate and then if you look in the mirror, it's the piece that's hang down in the mouth. that's your soft palette. that jabs in the back of your throat and gets occluded 500 times a night in somebody who has sleep apnea. >> and does that kind of research or science or medicine relate to your work in this case? >> yes, it's excreamily

pertinent to the case of mr. floyd, because, obviously, in sleep apnea, the problem is at the back of the throat and as we will see in mr. floyd's essential problem of where the obstruction is occurring is in the hypopharynx. it has a lot of overlap. >> we will come back to that hypophary xh x in a little bit. are you engaged if medical research? >> yes, i have been doing medical research since the early '80s, since 1981. >> what kind of research have you been doing? >> all of my research is related basical will i to breathing. so it is either looking at breathing in patients with lung disease people who have lung disease, who walk in the door to

the clinic and also patients who are in the icu and particularly patients who are requiring mechanical ventilation. then i do a lot of research that is absolutely nothing to do with clinical medicine, just to know how people breathe. >> have you authored a textbook on the subject of ventilation? >> yes, i authored a large textbook on mechanical ventilation that's called the principles and practice of mechanical ventilation. >> so i'm showing the cover of your textbook here on the camera. is this a book you are referring to? >> that is correct. >> 1,500 pages? >> correct. 1,500 pages, yeah. >> are you familiar with the lancet lancet medical journal? >> yes, the lancet is one of the top medical journals in the world. >> does the lancet medical

journal refer to this book as the bible of mechanical ventilation? >> yes, it has it is called that. >> have you authored other books also? >> yes, i have. >> roughly, how many? >> i think i published eight or nine on the books. >> and all related to res preparation or respratory failure? >> they're all on the lungs. >> have you published articles and abstracts also? >> yes, i have. >> i lose count but i think i published more than 750 probably or something like that. >> have you published in the new england journal of medicine? >> yes, i've published several articles in the nothing journal of medicine. >> are those two the most respected medical journals in the world? >> they are for clinical work, yes. >> have you also held editor positions at medical journals?

>> yes, i was editor-in-chief of the journal called the american journal of repracticetory medicine, it's the primary journal in the world for all lung disease, it's also the primary journal in the world for intensive care medicine. it's the official journal of the american thoracic society. >> have you taught and lectured outside of illinois and/or texas? >> yes. >> generally, where? >> i've lectured all around the world. i mean, i've lectured in more than 30 different countries around the world and probably the vast majority of states within the united states. >> well, minnesota is one of the states in the united states, how about minnesota? >> i have lectured in minnesota. i have been in the mayo clinic several times as a lecturer. >> were you given an award from the mayo clinic? >> yes, i was given an award called about power lecturer in

the mayo clinic. they give it out to one doctor every ten years. it's only to one doctor. it doesn't matter what specialty. so it could be around neurosurgery, gynecology, whatever. they just pick one person every ten years. >> was it for any, in particular, that you were recognized by the mayo clinic? >> no, just for my work as a researcher in clinical medicine. >> have you also published in basic science journals, such as the journal of applied physiology? >> yes, i published a lot of work on basic science that wouldn't necessarily be directly related to medicine in the journal of the applied physiology. >> jurors may not be familiar what physiology is as a science. could you generally explain it? >> fizz solg how the body works. you want to know the science of how it works. you want a deeper understanding of what are really the mechanisms that make the body

does what it does. >> within the field of physiology, is there a particular focus or interest you have? >> i am primarily interested in breathing, in the bigger area. so with breathing, that would mean how the brain regulates your breathing, how the brain sends signals down to the muscles that control your breathing, your diagram, your rib cage. and then how you expand your chest and how you overcome forces within your chest like resistance within your chest and all the rest of it to get air moving in and out of your lungs and then the particular forces that you generate in terms of the pressures within your chest that will enable breathing to occur with the ultimate purpose of getting oxygen in and getting rid of carbon dioxide. >> and do you consider this a part of the study of medicine? >> it's not quite a part of the study of medicine. it's really quite separate. because it's more the basic

physiology. so it's more in the realm of math and physics. but then it's applied over. to be a good the you need to have a good knowledge of science. but the science part is really separate from the medical part. it's to try and hone down on the science as best as possible. >> how long have you been working in respiratory physiology? >> since 1981, 40 years. >> what exactly drew you to the physiology of breathing? >> because i was going into pulmonary -- at that stage i knew i was directed. i spent five years doing lung disease and i just wanted to really know how you breathe and i wanted to come up with new knowledge. because everybody knew everything of how to breathe. that's how i found a lot of new stuff. >> so, doctor, do you know of

others kinds of in your field who have been studying respiratory physiology for 46 years? >> no, i moon i know enough of them along the way, i mean i would know no more than a hand. or less of people who are still doing physiology at the patient's bedside for the full 46 years. >> so, doctor, let's change subjects and talk a little bit about your experience of work as serving as an expert. as you served as an expert witness before? >> yes, i have. ? what types of cases? >> practically all of them have been in medical malpractice. i have done it both for the plaintiff side and the defense, for the physician side. >> have you ever been involved in a criminal case before? >> no, i have never been involved in a criminal case. >> have you testified in court before? >> i have testified in court. i don't keep track of the

numbers, but i suspect i have been in court about 50 times. >> would you tell the ladies and gentlemen if you are getting paid for your time in this case? >> no, i am not getting paid. >> and why is that? >> well, when i was asked to do the case, i thought i might have some knowledge that would be helpful to explain how mr. floyd died and sense i've never done this type of work in this nature before, i decided i didn't wish to be paid for it. >> so did you volunteer to the state of minnesota or did the state of minnesota call you? >> the state of minnesota contacted me. >> what were you asked to do, dr. tobin? >> i was asked to review the medical records related to the case. these were medical records from hennepin county and there were a number of interviews of people that were interviewed. i was given a list of these and,

primarily, it was related to looking at a large number of different videos. of course, the big part was that i needed to read on the scientific background of all the various aspects related to it. >> so let's talk about your opinion with respect to this case. have you formed an opinion to a reasonable degree of medical certainty on the cause of mr. floyd's death? >> yes, i have. >> would you please tell the jury what that opinion or opinions are? >> yes. mr. floyd died from a low level of oxygen and this caused damage to his brain that we see and it also caused a pea arrhythmia that caused his heart to stop. >> by pea, you mean pulseless electrical activity? >> yes. it's a particular form of an

abnormal beat of the heart arrhythmia, a particular form. >> is this what some persons might refer to as asphyxia? >> to me it's a low level of oxygen. other people talk about hypoxia. that is a latin term meaning a low level of oxygen. so all of this is just really other words for a phenomenon that is a low level of oxygen. >> have you formed an opinion to a reasonable degree of medical certainty as to what the cause is or was for the low level of oxygen in mr. floyd? >> yes, i have. >> would you tell us what that is? >> the cause of the low level of oxygen was shallow breathing. small breasts. small type of volumes, shadow

breasts that weren't able to carry the air through his lungs down to the essential areas of the lungs that get oxygen into the blood and get rid of the carbon dioxide. that's the alveoli at the bottom of the lung. >> doctor, using a short video that you use to explain to the jurors how oxygen gets to the lungs in the body. >> yes. >> i'm going to show you what's been marked as exhibit 915. can you describe first what that is? >> here we're looking at the lungs inside the body and we see here that you can see the windpipe up at the top the trachea and that splits into the bronchial tubes and also you can see the diaphragm down at the bottom. when the diaphragm contracts, it will still -- >> the jurors can't see it yet.

>> oh, i'm sorry. i apologize. >> i'm going to offer it exhibit 950. >> 950 is received. >> yes, please proceed. we will display it so the jurors can see it. >> okay. so now we're looking and you can see the contraction of the diaphragm, that's the pink area at the bottom. we see air going down to the windpipe and then proceeding down to the bronchial tubes and then it's going to continue down the bronchial tubes to reach out to the air sacs, which is the alveoli. we see we are moving down here. these are the grape-like structures at the bottom. this is where all the action occurs. the oxygen goes across those air sacs and it's expelled back out. so that's everything in a very

rapid video. >> so then what do you -- what happened in the case of mr. floyd that relates to the shallow breathing that resulted in his low oxygen? >> so, there are a number of forces that led to his, the size of his breath became so small and so there are a series of forces higher up that are leading to that and the main forces that are going to lead to the shallow breath are going to be that he's turned prone on the street, that he has the handcuffs in place combined with the street and then that he has a knee on his neck and then that he has a 93 on his back and down his side. all of these four forces are ultimately going to result in the low tidal volume which gives you the shallow breasts that we saw here. so the air will not be able to reach those air sacs we just saw

in the video where the oxygen is exchange and the carbon dioxide is removed. >> doctor, is there a concept that in the respiratory medicine field known as dead space? >> yes, there is. >> how does that relate to mr. floyd? >> so if you think in the video back all the way until you saw those clusters of grapes, where you saw the blood surrounding the alveoli, everything up to there is dead space. so as you are breathing in, you breathe in through your nose, your mouth through your windpipe, down to the bronchial tubes, radiating out until it reaches the air sacs. up until you get to the air sacs, it's all dead space. the reason we call it is because no objection jen can get across the bronchial tubes. no carbon dioxide can get through. the only place that that gets across is those grape-like structures. so everything in the lungs before that is dead space.

>> so you mentioned several reasons for mr. floyd's low oxygen and i just want to capture those for the jury and then we'll talk about them. you mentioned one handcuffs and the street. right? >> correct. >> you mentioned knee on the neck? >> yes. >> sorry for my writing. i didn't get an a in school. the prone position? >> yes. >> and then the knee on the back arms and side. were those the four? >> yes, these are the four. >> okay.

>> so we want to talk about each of these. but before we do that, might it be helpful for explaining your testimony to the jury for them to see the relative positioning of the various officers on mr. floyd's body when he was subdued on the ground? >> yes, that would be helpful. >> did you prepare an illustration to show the relative position of the officers on the ground? >> yes, i did. >> let me show you what has been marked as exhibit 949. could you just tell us just describe generally for the record what it is? >> i watched the videos at certain segments of the videos hundreds of times and it's very difficult to kind of get an overall view of where everybody is positioned because you are seeing different videos from different angles. and so the artist has taken all the different videos here and he's combined them into one

moment in time and you can see here and also he would remove the police vehicle so you are going to get a better view. so you are looking kind of at a bird's eye view of where mr. floyd is lying and where the officers are positioned in relationship to mr. floyd. >> all right. >> so that the purpose of this is to show the relative positions of the officers? >> correct. >> your honor, we would offer exhibit 949. >> any objection? >> no objection. >> 949 is received. >> so at what point in time did you say, told us this is at a particular point in time? >> right, this is at the particular point in time. i don't remember the exact minute, second, at the top of my head. >> 8:21 and 44 seconds? >> yes.

>> okay. so let's walk through exhibit 949, perhaps, if we can. doctor, tell us what we are seeing. >> okay. now you can see the car is being rotated. you are able to see officer chauvin. you are able to see officer king and an officer laying down at his feet. you see underneath mr. floyd, now the car is rotated. now the car has been removed and so you are able to see how they're positioned at different

points in terms of officer chauvin with his left knee on the neck, his right knee on mr. floyd's arm and chest and then you can see here officer lane holding his legs and then you can see officer king with his knee on his torso. >> so this represents a snapshot in time as you told us. did the officers' position change from time to time while they were on the ground? >> yes, the officers positions changed over time and also the position of mr. floyd changed over time and these become relevant in how we evaluate everything. >> and was it something that factored into your analysis then? >> yes. >>. >> did you consider where mr. chauvin's left knee was during the encounter? >> yes.

for offense chauvin's left knee is virtually on the neck for the vast majority of the time. >> and when you say vast majority, are you able to -- >> more than 90% of the time in michael calculations. there are certain times where it becomes difficult because you don't get a good view of where it is. so, for example, i know that an officer chauvin's right knee is on his back 57% of the time. the reason i'm not able to say for the 43% is that i don't get a good view. other times i don't have a good view of exactly where it is. >> so did you focus on the first five minutes and few seconds? >> yes, i focused on the first five minutes 3 seconds because that is up to the time that we see evidence of brain injury. >> so if mr. chauvin's right knee was on his back from time

to time and other times it was placed where? in your observation? >> it was placed on his arm or and then rammed into mr. floyd's left chest. so really whether you are making a distinction of whether the knee is on the chest per se or whether it's on the left arm and rammed in against the left cleft from the point of view of breathing, the effects are extremely similar. >> so let's turn to the, number one, on the -- >> [ inaudible question ]. >> oh, yes. i wanted to turn back to the notes that the number one thing written down for the reasons you told us were floyd's low oxygen, handcuffs and the street to talk about the first?

>> yes. >> could you first, dr. tobin, tell us how these various mechanisms, the four you discussed, handcuffs in the street, knee on the neck, prone position, knee on the next, back, knee on the back, arm and side. how do those mechanisms fall into your work of either respiratory physiology or clinical medicine? >> they don't have an awful lot to do with clinical medicine, but they are directly related to my work in physiology. so in understanding the forces that the body has to cope with these become, these are crucial in terms of the various forces that are involved in physiology. >> so then turning to the first one in handcuffs and the street, the very first one. what is the effect of the

handcuffs and in the context of what happened to mr. floyd? >> the handcuffs are extremely important in mr. floyd. but the handcuffs on their own just handcuffs per se are not that important, it must be the handcuffs combined with the str. it's because of the positioning of the handcuffs at the back, then how he is manipulated with the handcuffs by both officer chauvin and by officer king, how they manipulate the handcuffs. and they are pushing the handcuffs into his back and pushing them high. then on the other side, you have the street. so the street is playing a crucial part, because he is against the hard asphalt street. so the way they're pushing down on his handcuffs combined with the street, his left side -- it's particularly the left side we see that. it's like the left side is in a vice. it's totally being pushed in,

squeezed in from the street at the bottom and then from the way that the handcuffs are manipulated. it's not just the handcuffs. it's how the handcuffs are being held, how they're being pushed, where they're being pushed that totally interfere with central features of how we breathe. >> mr. floyd then is pancaked between the pavement underneath him and force on top of him? >> precisely. >> could you help us to explain how this mechanism, the handcuffs and the street, how does that explain the shallow breathing that you describe? >> this gets back to how we breathe. this is fairly simple. the way we breathe, we have two big muscles that help us with breathing. we have the diaphragm and the rib cage muscles. the diaphragm does about 70% of

what we need for breathing and about 30% of it comes from the rib cage. when the diagram contracts or the rib cage contract, they expand the chest. when you expand the chest, then air flows in from outside and it's coming in. that's all that happens on inspiration. to expand the chest, there's two crucial actions that have to happen. we have referred to these by the term pump handle and buckle handle. buckle handle is simple. if you have a regular buckle you carry water with and you lift up the handle of the bucket, the handle comes up like this. when you contract your diaphragm, you are performing a bucket handle movement on the rib cage. you contract your diaphragm like that. each time as you inspire, you can see it yourself, each of you

in the jury. you see your rib cage is going outwards. that's a buckle handle movement. the second movement that you have is called is the pump handle. this reflects through an old water people pump that would be yard for pumping out water. so you have the handle at the top of the pump. you lift up the handle of the pump each time and the water comes out the spout at the bottom. so you are filling up your container of water. with that action, you are lifting up. this refers to the front to back movement of the chest wall. with the pump handle, your chest goes out with each breath. so you can do it yourself. as you take a deep breath, you can feel front to back you are expanding your chest, front to back expansion of your chest is with your pump handle.

at the same time, you are doing both of them at the same time. at the same time you are doing that, your chest is expanding from side to side. that's with your buckle handle. both of these are occurring. these are vital. without these, you can't breathe. if you don't have the buckle handle working and the pump handle working, there's nothing working. there's no air going to get in there. >> doctor, do you have a photograph that you brought that would help to better understand the pump handle and buckle handle? >> yes. >> let me show you what's been marked as state's exhibit 951. do you recognize what this photograph depicts? >> yes. >> is it an accurate portrayal of a certain incident? >> yes. >> would it help to explain the testimony? >> yes. this is an event that happened in england -- >> one moment.

>> we offer exhibit 951. >> any objection? >> i have an objection. can we have a sidebar? >> there's now a sidebar happening as you have been watching the testimony here live in minneapolis of the murder trial of derek chauvin. dr. martin tobin, a pulmonologist, critical care specialist testifying about what he believes the cause of death was and describing what he has seen.

a detailed description you heard from dr. tobin, as we were listening to, the placement of the handcuffs behind george floyd's back. i want to bring in shaq brewster outside the courthouse. we don't know how long the sidebar will go. i may have to interrupt you. what are your takeaways so far? >> reporter: you heard the doctor there. he said -- he gave two big opinions. one that he said, george floyd died from a low level of oxygen. it looks like the judge is back. >> we will listen in. >> doctor, in this case, were you able to observe whether mr. floyd's breathing was impacted by the handcuffs and the placement on the street? >> yes, i was. >> what did you observe, dr. tobin? >> what i observed is particularly in terms of the hands of the police and the

handcuffs, particularly on the left side. so they were forcing his left wrist up into his chest, forcing it in tight against his chest, forcing it high up. you have to keep in mind that the opposite side of this is the street. so he was being squashed between the two sides. so this meant that he couldn't exert his pump handle. the street totally blocked his pump handle. there was no way he could do any front to back movement. again, the way they were pressing in on the back, there was absolutely no way that he could do any front to back movement. then in addition, because of the knee that was rammed in against the left side of his chest, sometimes the knee was down on the arm or in against the chest. so this would have the same affect. basically, on the left side of

his lung, it was almost like a surgical pneumonectomy. it was almost as if he removed the lung, but along those lines. there was little opportunity for him to be able to get any air to move to the left side of his chest. he was going to be totally dependent on what he would be able to do with the right side. >> have you selected any footage from the body-worn cameras that you feel depicts mr. floyd's struggles to breathe? >> yes. >> i'm going to show you what's been marked as state's exhibit 944. first, would you describe what it is? >> what you are seeing here is -- >> the jurors aren't seeing it. just describe it for the record. >> what it is. >> they will not see this. i'm describing what i am seeing? >> for now. >> that's fine.

what i'm seeing is that his left hand is being grabbed by the police officers. so that's a handcuffed left hand. it's being pushed into his chest. he is not able to expand that. in addition, what i am seeing -- >> only the foundation. >> i apologize. >> let's hold off. >> my misunderstanding. >> we offer exhibit 944. >> 944 is received. >> now the jurors can see it. >> i apologize. >> no, no. it was all right. would you tell us, what's the significance? >> now you are able to see here with the yellow arrow, you are able to see that the officer is holding mr. floyd's left hand. he is holding it very firmly. there's a very firm grasp on it. mr. floyd's left hand is being

pushed in against his chest. also, we are able to see on the side that officer chauvin's knee is coming in. that's compressing in against his side as well. the ability to expand his left side here is enormously impaired. also, you are seeing that the size of the chain between the two -- the right side and the left side is very short. his left arm is also being pulled over. so it's preventing him also from expanding the right side. i have been focusing on the bucket handle and the pump handle on the left. but you can also see here that these are impaired, his ability to expand his chest. of course, the key factor you must keep that's in a sense seen here in one sense is the street. the street is