Probe launched into key witness who said Derek Chauvin didn’t kill George Floyd

Now that Derek Chauvin has been found guilty, an investigation is being launched into one of the key witnesses who said the officer didn’t kill George Floyd.

A key witness in Derek Chauvin’s murder trial will have 17 years’ worth of his in-custody death reports independently reviewed after he testified that the former Minneapolis police officer was not responsible for the death of African American man George Floyd.

Dr. David Fowler, a retired forensic pathologist and former chief medical examiner of the state of Maryland, was put on the witness stand as a medical expert by Chauvin’s defence lawyer, Eric Nelson.

In court he said Mr Floyd’s death was caused by underlying health conditions and illegal drugs — conclusions that contradicted those of medical experts introduced by the prosecution.

Those experts said the 46-year-old African American died of hypoxia, or a lack of oxygen, while being held facedown and handcuffed on the street with Chauvin’s knee on his neck for more than nine minutes.

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Former Minneapolis police officer Derek Chauvin was found guilty on all charges. Picture: AFP

The South African-born Dr. Fowler however said Mr Floyd had an enlarged heart and a “significant narrowing of all of his coronary arteries”.

He said fentanyl and methamphetamine ingested by Mr Floyd were contributing causes along with “the potential of a carbon monoxide role”, and added that Mr Floyd was held down next to the exhaust pipe of a running police car.

Prosecutors called Martin Tobin, a pulmonologist, to rebut Fowler’s testimony and he said he had found no evidence of carbon monoxide poisoning.

Now that the trial is over, the American medical community has turned on Dr. Fowler after being alarmed by his testimonies during the four-week legal process.

Washington, D.C.’s former chief medical examiner Dr. Roger Mitchell Jr., wrote an open letter calling for investigations into Dr. Fowler’s medical license, as well as a review of the Maryland medical examiner’s office under Dr. Fowler’s leadership. At least 458 physicians across the USA have signed the letter.

They blasted his testimony about Mr Floyd’s cause of death — and especially the suggestion that carbon monoxide exposure may have contributed to it — as “baseless, revealed obvious bias, and raised malpractice concerns.”

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Dr. David Fowler is a retired forensic pathologist and former chief medical examiner of the state of Maryland. Picture: Court TV

They wrote that Dr. Fowler’s opinion that Mr Floyd’s death should be classified as “undetermined” was outside the standard conventions for investigating and certifying in-custody deaths, adding that it raises concerns about his previous handling of such cases.

“Our disagreement with Dr. Fowler is not a matter of opinion. Our disagreement with Dr. Fowler is a matter of ethics,” it reads.

Dr. Fowler has defended his work, telling the Baltimore Sunthat he was not solely responsible for autopsy conclusions and that he worked with a large team of forensic pathologists to arrive at them.

“I stand behind the outstanding work that all of our dedicated staff at the Maryland State Medical Examiner’s Office performed during my tenure as the Chief ME,” he toldThe Washington Postin a statement.

He said his opinion in the Chauvin trial “was formulated after the collaboration of thirteen other highly experienced colleagues in multiple disciplines” and that it “set an ethical standard for the work needed in sensitive litigation.”

Overnight, Maryland officials revealed they will be conducting an independent review of reports of deaths in police custody during Dr. Fowler’s tenure as chief medical examiner of Maryland.

The investigation will call into question the validity of all of Dr. Fowler’s in-custody death reports in the role.

George Floyd’s death has sparked calls for police reform in the USA. Picture: Angela Weiss / AFP

Meanwhile, Chauvin will be sentenced on June 16 for the murder Mr Floyd.

The 45-year-old ex-officer — who knelt on Floyd’s neck for more than nine minutes — faces up to 40 years in prison after being found guilty of all charges this week over the death of the unarmed man.

The crime was recorded by a bystander whose video shocked the world, triggering mass protests across the United States and beyond, while also prompting a national reckoning on racial injustice and police brutality.

Mr Floyd, 46, was killed as he lay face down and handcuffed, saying repeatedly “I can’t breathe.” The case prompted some police reforms, but advocates including President Joe Biden say more is needed.