A state corrections spokesman said Anthony McKinney, 53, was found unresponsive and alone in his locked cell Tuesday at the Dixon Correctional Center, the Chicago Tribune reported. No foul play was suspected, but the official cause of death had not been determined, the newspaper said.
McKinney had alleged he confessed to the 1978 shotgun slaying of a security guard in the Chicago suburb of Harvey only after police beat him with pipes. He was 18 at the time.
"The criminal justice system failed Anthony," said Karen Daniel, McKinney's lead attorney who suggested he may have been exonerated if not for delays in the legal process.
2014: NFL Cheerleaders [PHOTOS]
White House intruder had a knife