MINNEAPOLIS – A medical expert in breathing physiology testified in the murder trial of Derek Chauvin that Chauvin and other former police officers held George Floyd back – handcuffed behind his back, face down on the floor, one knee behind his neck – stopped him to breathe properly.
Dr. Martin Tobin said the cause of Floyd death is hypoxia, or low oxygen levels that lead to suffocation or asphyxiation. The overall effect of the reluctance was almost “like a surgeon went in and removed the lungs,” he said, referring to Floyd’s left lung.
“A healthy person exposed to what Mr. Floyd was exposed to would have died as a result of what he was exposed to,” Tobin said.
Chauvin is charged with second degree murder, third degree murder, and second degree manslaughter in Floyd’s death. The defense argues Floyd died from the effects of the drugs in his system and underlying medical problems, but prosecutors say Floyd was killed by Chauvin’s knee on his neck for more than nine minutes.
Keep up to date with the Derek Chauvin Study: Sign up for Text messages of key updatesFollow the USA TODAY Network Reporter on Twitter, or Subscribe to the Daily Briefing Newsletter.
Last update:
- Dr. Martin Tobin, a doctor whose research focuses on breathing, was interrogated by senior defense attorney Eric Nelson on Thursday afternoon.
- The jury has heard from 31 witnesses so far – all called by prosecutors.
- Lawyer The interview returned to the subject of Floyd’s drug use On Wednesday. Nelson suggested that Floyd said the words “I ate too many drugs” during his battle with the police on Memorial Day and played a few seconds of incomprehensible police camera audio for witnesses.
- Wednesday afternoon, Two forensic scientists said pills were found Floyd had contained methamphetamine, a stimulant, and fentanyl, a synthetic opioid, in the SUV and police car that day. A toxicological report found both drugs in Floyd’s system after his death.
The doctor who studies breathing says Floyd died of “low oxygen levels.”
Dr. Martin Tobin, a doctor who has worked in respiratory physiology for 40 years, testified Thursday that Floyd died of “low oxygen levels” that damaged his brain and caused an abnormal heartbeat.
Tobin said he watched videos of Floyd’s arrests “hundreds of times” and found that Chauvin’s left knee was on Floyd’s neck most of the time. The combination of Floyd handcuffed behind his back, the officers’ manipulation of the cuffs and the sidewalk below Floyd affected Floyd’s ability to breathe, Tobin testified.
“It’s like the left side is in a vise. It’s totally pushed in, pushed in by the road below and then by the way the handcuffs are tampered with,” he said. “That completely affects the central characteristics of our breathing.”
Tobin said pictures from the videos show Floyd trying to use his right fingers and knuckles to push up the right side of his lungs to get air into them. “That tells you he’s used up his resources and is literally trying to breathe with his fingers and knuckles,” said Tobin.
Tobin looked at the jury as he testified, and each juror made notes.
Tobin said when the toe of Chauvin’s boot was off the ground, 91.5 pounds of weight fell directly on Floyd’s neck. When Chauvin’s toes were on the ground, he said Floyd had 86.9 pounds on his neck.
Tobin said Floyd’s lung capacity decreased by nearly a quarter when he was prone. As soon as Chauvin puts his knee to Floyd’s neck, his lung capacity drops by 43%, Tobin calculated.
“Now the work that Mr. Floyd has to do is huge,” said Tobin. “With every breath he has to fight against the street, fight with the small amounts he has and try to raise the officer’s knee with every breath, and also has to raise the action of the officer inflating his arm – the handcuffed one cuffed arm. “
During the first four minutes and 51 seconds of suppression, Floyd was able to speak, which meant oxygen was reaching his brain, Tobin said. After five minutes and three seconds, Floyd kicked a leg in an extended position – a sign that he had suffered brain damage. After that point, the movement of Chauvin’s knee was no longer relevant as the damage was being done.
“You are seeing a fatal injury to the brain from a lack of oxygen,” said Tobin.
Tobin testified that Floyd passed out at 8:24 p.m. As an intensive care doctor, Tobin said he could tell a patient who had passed out “how to snap your eyes or how to tighten the muscles on your face”.
“You can see from his eyes that he’s conscious. Then he’s not,” said Tobin. “This is the moment when life goes out of his body.” Tobin said Floyd took his last breath at 8:25 p.m.
“The knee stayed on the neck for another 3 minutes and 2 seconds after we got to the point where there was no more ounce of oxygen in the body,” said Tobin.
Addressing defense arguments that Floyd died due to poor health and drug use, Tobin said Floyd’s breathing was not affected by fentanyl in his system or underlying health problems.
During cross-examination, senior defense attorney Eric Nelson highlighted the inequality between Tobin’s medical expertise and the training of Minneapolis police officers “who are not even rescue workers.”
Tobin also said that after questioning, he knows that Floyd’s autopsy showed no signs of bruising or damage to the hypopharynx – a part of the throat that Tobin previously said was constrained by officials’ reluctance.
Nelson tried to discredit Tobin’s testimony by questioning the assumptions underlying his calculations. Tobin said he made “very few assumptions” despite Nelson’s efforts to say otherwise. “They’re not theoretical,” said Tobin.
Unlike some previous witnesses, Tobin pushed back against Nelson’s attempts to get brief yes or no answers. He also corrected the defender at times.
Addressing defense arguments that Floyd died due to poor health and drug use, Tobin said Floyd’s breathing was not affected by fentanyl in his system or underlying health problems. He added that it took another five minutes to get to the hospital.
When questioning returned to prosecutors, Attorney Jerry Blackwell said, “If you factor in all of the nanoseconds and milliseconds in the 5 minutes and 3 seconds, where was Mr. Chuavin most of the time?”
“On Mr. Floyd’s neck, back and arm,” said Tobin.
“Don’t keep changing?” Blackwell said.
“No,” said Tobin, adding, “the cause of death is the low oxygen levels that caused the brain damage and caused the heart to stop.”
“Due Diligence”: Prosecutors say Chauvin betrayed politics by not helping Floyd
Prosecutors said Chauvin was not only responsible for Floyd’s death, but failed to perform his basic care duty when Floyd was in medical emergency and then stopped responding.
Several officers from the Minneapolis Police Department testified that Chauvin violated the department’s guidelines by failing to bring Floyd to his side to help his breathing after being pinned on the floor undercover.
“When someone is in our care, we have an obligation to take care of them,” Minneapolis police chief Medaria Arradondo told the jury. That’s true even when an officer uses defense tactics, the chief said. “You are still in our care,” he said. “You have rights.”
The defense has argued that Chauvin and the other officers couldn’t take care of Floyd because they were distracted and threatened by a crowd of noisy, angry onlookers. “As the crowd grew, so did their anger,” senior defense attorney Eric Nelson told the jury. Continue reading.
Surveyor Sgt. Jody Stiger says Chauvin used “lethal” force
Sgt. Jody Stiger, a Los Angeles Police Department officer who has completed approximately 2,500 violence use tests in his career, told jury this Wednesday Chauvin used “fatal” violence against George Floyd and held his knee by Floyd’s neck for more than nine minutes.
Stiger said the initial violence against Floyd was appropriate because Floyd resisted arrest when officers tried to get him into their patrol car. After the officers forced Floyd to the ground, “they should have de-escalated the situation,” Stiger said. Instead, officials continued to exacerbate the situation, he said.
Stiger said the number of officers on the ground outweighed the threat posed by Floyd, who did not actively resist in the prone position. He said “no force should have been used after being in this position.” But the constant pressure Chauvin put on “increased the possibility of death,” he said. More here.
