Christopher Abernathy freed by DNA tests in 1984 murder of Kristina Hickey

CHICAGO (WLS) -- After spending almost 30 years in prison for a crime he did not commit, Christopher Abernathy was freed Wednesday.

The 48-year-old man walked out of Stateville Prison a free man after a judge vacated his life sentence for the 1984 sexual assault and murder of a 15-year-old girl in the south suburbs.

Abernathy, then a teenager with learning disabilities, signed a statement confessing to the rape and murder of Kristina Hickey, a sophomore at Rich East High School. She had been raped and murdered

"They held him for two days in the police station and questioned him, and he was finally coerced into signing a false confession," Lauren Kaeseberg, Illinois Innocence Project, said.

Last year, Abernathy's attorneys asked for DNA testing on eight pieces of evidence from the crime. The State's Attorney agreed. Result?

"To be clear, there is no DNA match that would lead to Mr. Abernathy," Cook County State's Attorney Anita Alvarez said.

With DNA clearing him, the charges against Abernathy were dismissed.

Abernathy said he was "scared" when asked about being let out of prison and little more. His attorneys say that's understandable after spending your entire adult life in prison. His mother visited every week for 29 years.

"She never gave up on her son. And she never missed a date. And now she can spend the rest of her life with her son, and that's what she wanted," attorney Damon Cheronis said.

So who killed Hickey, who was murdered after a high school choir performance?

"We think there's some potential evidence that we can follow," Alvarez said. "Can't really say much more than that. But as of yesterday, it's being looked at."

The DNA results are consistent on all eight pieces of evidence kept after the murder suggesting that there was a single killer. Those findings were run through the state's DNA data base, but no matches. A cold case team now goes to work on a 30-year-old murder as Abernathy tries to start life anew.