A man who spent nearly 40 years in prison for a murder he did not commit filed a federal lawsuit on Tuesday against the city of Cleveland and the police officers who he says helped frame him in 1975.

Ricky Jackson was convicted at age 18 along with two others because of the testimony of a 12-year-old boy. Jackson, 58, was exonerated in November after that witness, a man now in his early 50s, recanted his testimony.

The witness, Eddie Vernon, said in 2013 that police detectives threatened to put his parents in jail and coerced him into implicating Jackson and brothers Wiley and Ronnie Bridgeman in the slaying of salesman Harold Franks outside a corner store.

Jackson and the Bridgemans received death sentences that were later commuted to life in prison. Jackson’s attorneys say their client is believed to have served the longest prison term in the US for someone wrongfully convicted.

The lawsuit alleges that eight officers, including detectives and their supervisors, were involved in framing the three. Some of the officers are now dead.

A statement from the Chicago law firm that filed the lawsuit said Jackson’s mother, father, stepfather and other relatives died while he was incarcerated and that he was assaulted and injured physically while behind bars.

“This lawsuit seeks compensation for that grievous injustice,” attorney Jon Loevy said in the statement. “We now know substantially more about the fallibility of eyewitness identifications. Too many people have been sent to prison wrongfully based on bogus identifications.”

A spokesman said Tuesday that the city of Cleveland doesn’t comment on pending litigation.

In March, the state of Ohio paid Jackson just over $1m in compensation for the decades he spent in prison.

The lawsuit details how officers coerced Vernon into implicating the men. Vernon has stated, and the lawsuit repeats, that he was on a school bus and heard the fatal gunshots but did not see the shooting itself. Detectives ignored a suspect who had been implicated by informants and his own mother, the lawsuit said. That suspect was convicted a few years later of multiple counts of armed robbery.

Jackson was roughed up during a police interrogation, the lawsuit said. Two detectives “repeatedly put a phone book on Mr Jackson’s face and other areas of his body and hit him through it so that it would not leave any marks,” the lawsuit says, but Jackson continued to deny he killed anyone.

After Vernon failed to pick out Jackson and the Bridgemans from a lineup, detectives yelled and screamed at Vernon and threatened to put his father and his ill mother in jail unless he identified the men as Franks’s killers, the lawsuit says.

The lawsuit alleges that detectives helped fabricate Vernon’s trial testimony and falsified investigative reports.

