George Floyd died from low oxygen levels, respiratory expert testifies
George Floyd died from low oxygen levels while being restrained by ex-Minneapolis cop Derek Chauvin — and a healthy person would have suffered the same fate if put in the same position, a world-renowned respiratory expert testified Thursday.
Dr. Martin Tobin delivered the damning testimony on the ninth day of Chauvin’s trial for the May 25, 2020, killing of Floyd, who was arrested for passing a counterfeit $20 bill.
“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 [pulseless electrical activity] arrhythmia that caused his heart to stop,” Tobin said.
The combination of Floyd, 46, being held face-down on the street, handcuffed behind his back and Chauvin’s knees pressed against his neck and shoulder for 9 minutes and 29 seconds made it impossible for him to breathe, the Dublin-born doctor told jurors in Minnesota’s Hennepin County District Court.
“A healthy person subjected to what Mr. Floyd was subjected to would have died,” the expert said during direct examination by prosecutor Jerry Blackwell. “It was almost to the effect that a surgeon had gone in and removed the lung…It’s like the left side is in a vise.”
During the deadly encounter, Floyd said “I can’t breathe” 27 times and called out for his mother before he stopped moving.
“When you have to breathe through a narrow passageway, it’s like breathing through a drinking straw but it’s much worse than that,” said Tobin, describing Floyd’s desperate gasps for air.“
Tobin, who specializes in pulmonary and critical care medicine, reviewed the haunting footage of Floyd’s arrest — which went viral and sparked worldwide protests — to reach his conclusions.
“At one point in the video, Chauvin shifted his knee, putting greater pressure on Floyd’s airway,” the doctor said. “Half of his body weight and half of his gear weight, that’s 91.5 pounds, is coming down on Mr. Floyd’s neck,” he told jurors.
Chauvin, 45, kept his knee pressed against his neck for more than three minutes after Floyd had gone limp.
Prosecutors have argued that Chauvin used “excessive and unreasonable” force, while the defense contends that Floyd died as a result of drug use and a heart ailment. He had fentanyl and speed in his system at the time of his death.
But Tobin said that Floyd’s respiratory rate was normal — not depressed in the way it would be if he had suffered a fentanyl overdose. The accumulation of carbon dioxide in his blood, which can be a result of a drug overdose, was consistent with the buildup that occurs from lack of ventilation, he said.
Chauvin, who was fired one day after the tragic confrontation, is charged with second-degree murder, third-degree murder and second-degree manslaughter. He faces up to 40 years in prison on the top count.
Three other former Minneapolis police officers — Tou Thao, Thomas Lane and J. Alexander Kueng — are due to stand trial on charges of aiding and abetting murder and manslaughter in the case.
Dr. Andrew Baker, the medical examiner who performed Floyd’s autopsy and a crucial expert, is expected to take the stand on Friday.


