Prude's family this week released body camera footage from his arrest, showing a group of officers putting a hood over his head - apparently to prevent his spit from possibly transmitting the novel coronavirus - as he knelt on the ground, handcuffed and naked.
Prude's family has called for the arrest of the officers involved in his death seven days after the incident on March 23 in the upstate New York city. Prude was 41.
The Monroe County medical examiner ruled Prude's death a homicide caused by "complications of asphyxia in the setting of physical restraint," according to an autopsy report, the New York Times reported.
The autopsy report said "excited delirium" and acute intoxication by phencyclidine, or the drug PCP, were also contributing factors to his death, the Times reported.
"Mr. Daniel Prude was failed by our police department, our mental health care system, our society, and he was failed by me," Rochester Mayor Lovely Warren, who is Black, told reporters. "I'm filled with grief, and anger at myself for all the failures that lead to his death."
Warren, who said she was not made aware of the circumstances of Prude's death until August, condemned the death as an act of racism.
"Institutional and structural racism led to Daniel Prude's death. I won't deny it, I stand before it, and I call for justice upon it," Warren said.
Prude's asphyxiation occurred two months before the death of George Floyd at the hands of Minneapolis police, which spurred international protests against police brutality and racial injustice in the United States.
Prude's family obtained body camera footage after filing a freedom of information act request, CBS-affiliate WROC-TV reported.
Rochester police chief La'Ron Singletary, who is Black, told reporters on Wednesday that internal and criminal investigations were underway.
Rochester police declined further comment on Thursday, and a lawyer for Prude's family did not respond to a request for comment.
The office of New York Attorney General Letitia James is investigating, as state law requires whenever police are involved in a civilian's death.
'YOU'RE TRYING TO KILL ME'
In the video, an officer placed a "spit hood" over Prude's head. Prude could be heard shouting, "Take this...off my face!" and "You're trying to kill me!" before his shouts turned to cries and became muffled. Officers were heard saying "Calm down" and "stop spitting."
Later, the video showed an officer kneeling on Prude's back while Prude was silent and snow fell around them. Someone was heard saying, "start CPR." Minutes later, the video showed Prude being loaded into an ambulance on a stretcher.
Activists were planning protests in Rochester and New York City's Times Square on Thursday calling for the officers to be charged.
Protests broke out on Wednesday in downtown Rochester, a city near Lake Ontario about 300 miles (480 km) north of New York City. Police released pepper spray on the demonstrators and arrested nine people, the Democrat and Chronicle reported.
Mayor Warren said she was joined by City Council in calling for the charges against the protesters to be dropped on Thursday.
Prude's family told reporters that Prude had been struggling with mental health. His brother, Joe Prude, said he had called police because he was worried when his brother left home that night.
"I placed a phone call for my brother to get help, not for my brother to get lynched," Joe Prude said.
