MINNEAPOLIS – A medical expert in respiratory physiology testified in the Derek Chauvin murder trial that the way Chauvin and other former police officers restrained George Floyd – handcuffed behind his back, face down, with one knee on his neck – prevented him from breathing properly.
Dr Martin Tobin said the cause of Floyd’s death was hypoxia, or a low level of oxygen that led to asphyxiation. Tobin testified that the combination of the handcuffs, the handling of the handcuffs by the officers, and the sidewalk under Floyd combined to interfere with Floyd’s ability to breathe.
The overall effect was almost “as if a surgeon had walked in and removed the lung,” he said, referring to Floyd’s left lung.
The questioning returned to the subject of Floyd’s drug use on Wednesday. His girlfriend Courteney Ross told jurors last week that the two became addicted to opioids four years ago after being prescribed chronic pain medication. Like millions of Americans, they tried to stay clean but failed, she said.
Defense attorney Eric Nelson suggested that Floyd say the words, “I ate too many drugs” during his fight with the police on Memorial Day on Wednesday. He played several seconds of unintelligible police body camera audio for witnesses: one said he couldn’t understand Floyd’s words, and the other said he thought Floyd was saying “I don’t take drugs.”
In the afternoon, two forensic scientists said the pills found in Floyd’s SUV and police car that day contained methamphetamine, a stimulant, and fentanyl, a synthetic opioid. A toxicology report found both drugs in Floyd’s system after his death.
Chauvin is charged with second degree murder, third degree murder and second degree manslaughter in Floyd’s death. The defense argues that Floyd died from the drugs in his system and underlying medical issues, but prosecutors say Floyd was killed by Chauvin’s knee to his neck for more than nine minutes.
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- Dr Martin Tobin, a doctor whose research focuses on breathing, appeared on the witness stand Thursday morning.
- So far, jurors have heard from 30 witnesses – all named by the prosecution.
- Jurors attended several days of highly technical testimony on the use of force and chains of command, and a reporter in the courtroom on Wednesday noted that a juror may have fallen asleep.
- Expert witness Sgt. Jody Stiger, an officer with the Los Angeles Police Department who has conducted around 2,500 use of force reviews during his career, told jurors on Wednesday that Chauvin used “lethal” force on George Floyd and had kept his knee on Floyd’s neck for over nine minutes.
Doctor who studies breathing says Floyd died of ‘low oxygen’
Dr. Martin Tobin, a physician who has worked in respiratory physiology since 1981, testified Thursday that Floyd died from “low oxygen levels,” which caused damage to his brain and an abnormal heartbeat.
Tobin said the cause of Floyd’s death was hypoxia, caused by Floyd having to take shallow breaths that did not allow oxygen to travel to the lower lungs where gas exchange occurs.
Tobin said he watched videos of Floyd’s arrests “hundreds of times” and discovered that Chauvin’s left knee was on Floyd’s neck most of the time.
The fact that Floyd was handcuffed behind his back, the handling of the handcuffs by officers and the sidewalk under Floyd combined to interfere with Floyd’s ability to breathe, Tobin testified.
“It’s like the left side is in a vise. It’s totally pushed in, pressed down from the street down, then the way the handcuffs are handled,” he said. “It totally interferes with the central characteristics of the way we breathe.”
Tobin said the footage from the videos shows Floyd trying to use his right fingers and knuckles to push the right side of his lungs upward to get air in. “This tells you he’s exhausted his resources and he’s literally trying to breathe with his fingers and knuckles,” Tobin said.
Floyd’s position restricted a part of the airway called the hypopharynx, which is vulnerable because it’s so small, Tobin said.
As Chauvin pressed his knee into Floyd’s hypopharyngeal region, Tobin said, breathing became “enormously more difficult” than breathing through a straw. If the pressure had been continuous on the hypopharynx, it would have caused a heart attack or fit, Tobin said.
Tobin watched the jurors as he testified, and each juror took notes. At one point, Tobin asked them to feel their own necks to locate the hypopharynx, which sparked a sideways conversation between the prosecution and the defense. The judge told jurors that they did not have to follow his instructions.
Tobin has been an expert witness in numerous court cases, most involving allegations of medical malpractice. This is his first criminal case and he chose not to seek payment when the State of Minnesota contacted him because he felt he could contribute his knowledge.
The prosecution said Chauvin was not only guilty of Floyd’s death, but also failed in his duty to provide basic care when Floyd was in medical distress and then became unresponsive.
Several officials from the Minneapolis Police Department testified that Chauvin violated departmental policy by failing to move Floyd to his side to ease his breathing once he was held face down.
“When someone is in our care, we have an obligation to provide for them,” Minneapolis Police Chief Medaria Arradondo told jurors. This is true even if an officer applies defensive tactics, the chief said. “They are still in our care,” he said. “They have rights.”
The defense argued that Chauvin and the other officers were unable to deal with Floyd because they were distracted and threatened by a crowd of loud and upset passers-by. “As the crowd grew in size, their anger apparently increased as well,” lead defense counsel Eric Nelson told jurors. Read more.
Expert witness Sgt. Jody Stiger says Chauvin used ‘deadly’ force
Sgt. Jody Stiger, an officer with the Los Angeles Police Department who has conducted around 2,500 use of force reviews during his career, told jurors on Wednesday that Chauvin used “lethal” force on George Floyd and kept his knee on Floyd’s neck for over nine minutes.
Stiger said the initial force used on Floyd was appropriate because Floyd resisted arrest as officers attempted to get him into their patrol car. However, after the officers forced Floyd to the ground, “they should have defused the situation,” Stiger said. Instead, the officers continued to escalate the situation, he said.
Stiger said the number of officers at the scene outweighed any threat posed by Floyd, who was not actively resisting while in the prone position. He said “that no force should have been used after being in this position.” But the pressure continually exerted by Chauvin “raised the possibility of death,” he said. More here.