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Derek Chauvin’s Expert Witness Lays Out Defense Theory on Cause of George Floyd’s Death


A expert witness called by the defense in the murder trial of fired Minneapolis police officer Derek Chauvin, 45, argued that victim George Floyd, 46, died from pre-existing conditions.

“In my opinion, Mr. Floyd had a sudden cardiac arrhythmia [abnormal beating of the heart], or cardiac arrhythmia, due to his atherosclerotic and hypertensive heart disease–you can write that down multiple different ways–during his restraint and subdual by the police,” said Dr. David Fowler, former Chief Medical Examiner of Maryland, in testimony on Wednesday. Significant contributory conditions included fentanyl and methamphetamine in his system, and exposure to carbon monoxide from vehicle exhaust, and paraganglioma [a tumor], he said.

Fowler said there were so many elements at play that the manner of death was not clear.

As may be expected, this testimony contradicts the autopsy, which determined Floyd’s death was a homicide. Authorities acknowledged drugs in the Floyd’s system, and noted his prior conditions, but said the major factor was Chauvin kneeling on the man’s neck for so long during a fateful arrest on May 25, 2020.

Dr. Jonathan Rich, a state’s witness and cardiologist, testified that Floyd died neither of a “cardiac event” nor of a drug overdose.

Dr. Andrew Baker, who performed the autopsy of Floyd, said being held prone to the ground and handcuffed behind his back was too much for Floyd to take.

Another state’s witness, pulmonologist Dr. Martin Tobin, emphatically dismissed the role that fentanyl could have had in hindering respiration. Though the drug can cause this, it would be through the brain, he said. During redirect, he said that people go into a coma before they die of fentanyl, and Floyd was not in a coma.

“You know fentanyl is not causing the depression of his respiration,” the expert pulmonologist said. “What you’re seeing is that the increase in his carbon dioxide that is found in the emergency room is solely explained by what you expect to happen in somebody who doesn’t have any ventilation given to him for 9 minutes and 50 seconds. It’s completely explained by that.”

During cross-examination, prosecutor Jerry Blackwell worked to downplay the presence of carbon monoxide, and to emphasize Chauvin’s restraint of Floyd.

Fowler is currently a co-defendant in a lawsuit in which he is accused of covering up the actions of officers in the death of a Black teen who died in police custody.

Colin Kalmbacher contributed to this report.

[Screengrab on left via Darnella Frazier; screengrab on right via Law&Crime Network]

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