Eight police officers have been suspended, a day after an inquest ruled a man who died after being restrained was unlawfully killed.
Roger Sylvester was restrained "with excessive force"
Roger Sylvester, 30, died in 1999 a week after being restrained by eight officers from the Metropolitan Police.
The inquest said Mr Sylvester, who had mental health problems, had been held for too long, in the wrong position.
The Met said the suspensions, on full pay, were part of an ongoing investigation. The officers deny using
Mr Sylvester's family welcomed the suspensions, although they said they had come too late.
But the officers' representative organisation, the Metropolitan Police Federation, condemned the move.
Chairman Glen Smyth issued a veiled warning that it could lead to officers refusing to restrain the mentally ill in future.
The suspensions were pending a review by the Crown Prosecution Service, he said.
He said: "The decision to suspend does not, of course, imply any basis of criticism of any police officer.
"The Police Federation however regrets the decision."
He said the eight officers involved had provided "dedicated service" throughout their careers and they co-operated fully with the inquest.
He added: "There was no suggestion of bad faith in their treatment of Mr Sylvester."
He said the officers had acted "not simply in accordance with training, but also within recognised medical procedures".
Under those circumstances, he said, "if they are to be accused of unlawful killing, wider implications as to the continued participation of police officers in the restraint of the mentally ill will inevitably arise".
Mr Sylvester's brother, Bernard Renwick, said: "I am heartened by the decision...
"We have been asking for four and half years that the officers be suspended and investigated properly."
Deborah Cole, co-director of campaign group Inquest, said the Met should have been doing more - including addressing the training and guidance of officers.
"I would have hoped that alongside the suspensions there would have been an announcement of urgent action regarding these issues," she said.
Mr Sylvester was detained after being found naked and banging on the door of his own home in Tottenham, north London on 11 January 1999.
Police detained the struggling man under the Mental Health Act and took him to an emergency psychiatric ward at St Anne's Hospital, Haringey.
There, up to six of the eight officers restrained him and he stopped breathing while under restraint.
He never recovered, and died seven days later in London's Whittington Hospital.
The jury found Mr Sylvester died from brain damage and cardiac arrest, triggered and exacerbated by breathing problems which occurred during the restraint, and also cannabis-induced delirium.
The jury foreman said Mr Sylvester had been restrained too long, and more force was used than was reasonably necessary.
The officers denied the allegation, saying Mr Sylvester had been kept on his side in line with police restraint guidelines.
They also denied using excessive force, and it is expected that they will apply to the High Court for the verdict to be quashed and for a fresh inquest.
After the inquest the CPS said it would review its decision not to press charges against any of the officers involved.
Mr Sylvester's family said they were also considering their next steps, including the possibility of a civil prosecution.
The Metropolitan Police said it took Mr Sylvester's death very seriously and was working on ways to reduce deaths in custody.