Daniel Penny, 24, a US Marine Corps veteran, has turned himself on a manslaughter charge that could send him to prison for 15 years.
Manhattan prosecutors announced on Thursday they would bring the criminal charge against Mr Penny following the death of Jordan Neely, 30, on May 1.
Mr Penny turned himself in at a Manhattan police station on Friday morning.
Mr Neely’s death, captured on video by a freelance journalist, has raised an uproar over many issues, including how those with mental illness are treated by the transit system and the city, as well as crime and vigilantism.
Thomas Kenniff, one of Mr Penny’s lawyers, said his client turned himself in “voluntarily and with the sort of dignity and integrity that is characteristic of his history of service to this grateful nation”.
In a brief statement to reporters outside the police station, Mr Kenniff said that he expected an arraignment later on Friday and that the process “will unfold from there”.
Asked how Mr Penny was feeling, Mr Kenniff said his client “is dealing with the situation, like I said, with the sort of integrity and honour that is characteristic of who he is and characteristic of his honourable service in the United States Marine Corps”.
Mr Penny’s lawyers have said he acted in self-defence when he restrained Mr Neely.
According to an onlooker, Mr Neely, who is Black, had been screaming and begging for money aboard the train, but had not been physical with anyone.
Mr Penny, who is white, was questioned by police in the aftermath but was released without charges.
Friends of Mr Neely said the former subway performer had been dealing with homelessness and mental illness in recent years.
He had several arrests to his name, including the 2021 assault of a 67-year-old woman leaving a subway station.
A second-degree manslaughter charge in New York will require the jury to find that a person has engaged in reckless conduct that creates an unjustifiable risk of death, and then consciously disregards that risk.
The law also requires that conduct to be a gross deviation from how a reasonable person would act in a similar situation.
