CHICAGO (WBBM NEWSRADIO) — Four men are suing the City of Chicago, Chicago police and prosecutors for imprisoning them for more than 20 years for murders the evidence shows they did not commit.

They were known as the Marquette Park Four, arrested in 1995 and convicted of a double-murder and robbery. Charles Johnson, Larod Styles, LaShawn Ezell and Troshawn McCoy were freed a year ago this week after 20 years in jail.

Their attorneys said the conviction was based solely on false confessions.

Locke Bowman, head of the MacArthur Justice Center, said these things have happened over and over again. In fact, some of the officers involved in this case were also part of the Englewood Four case settled for $31 million.

“There is, if you go back in the records, almost no instance in which a Chicago police detective has ever faced any kind of discipline or adverse action from the city or department as a result of his involvement in a known wrongful conviction. Why is that?” Bowman said.

The lawyers said at least one of the officers is still on the force.

Now, the four are suing for damages. Charles Johnson was 19 when he was arrested. Larod Styles was 16 and said damage awards could help make up for what they went through.