CHICAGO (AP) — The FBI has released a report that accuses Chicago police of pressuring four suspects in a 1994 murder case as they gave prosecutors their statements.

The report unsealed Wednesday details the FBI's interview of former Assistant State's Attorney Terence Johnson, who worked with detectives to take statements in the investigation into the rape and killing of 30-year-old Nina Glover. Johnson also approved charges against the men.

Michael Saunders, Vincent Thames, Harold Richardson and Terrill Swift said in separate lawsuits that police and Cook County prosecutors pressured them. The men spent 15 years in prison before 2011 tests matched DNA from the victim's body to another man who was killed in 2008.

Peter Neufeld, a New York-based attorney for one of the men, said the report is evidence of "systemic misconduct."

"There's no reason that the misconduct we see in this case would be limited to just this case," Neufeld said.

Johnson said his boss pressured him to cooperate with detectives. He told federal investigators that detectives "coached and fed" witnesses and pushed the defendants into giving confessions that were eventually proven by DNA to be false.

"The strategy was to use the subjects against each other," the report contends. "They were told the detectives needed a witness, and if they were forthcoming and credible, they would be the witness."

No one else has been convicted in the attack.

On Wednesday, the Cook County Board approved a $5.6 million settlement with Swift, who also has tentatively settled with the city for an undisclosed amount. Attorneys for the city in the pending federal cases of the other three other men filed a motion asking the judge to set a settlement conference.