A convicted murderer has pleaded guilty to the 1983 killing of a 10-year-old girl in a case that led to death penalty reforms in Illinois.

Brian Dugan entered his plea Tuesday in Jeanine Nicarico's murder. He's already serving life in prison for two other murders.

Dugan offered to plead guilty if prosecutors agreed not to seek his execution. They've refused, but Dugan hopes to convince a jury or judge that he should be given a life sentence.

The Nicarico case has included convictions and death sentences for two men who were later exonerated, allegations of a massive frame-up and multimillion-dollar lawsuits. It was one of several that led former Gov. George Ryan to stop all Illinois executions in 2000.

Jeanine was home sick from school when someone kicked down her door. Her raped and beaten body was found two days later in a nature preserve.