Christopher Abernathy spent nearly 30 years in prison for the rape and murder of 15-year-old Kristina Hickey in 1984. Today, Abernathy, now 48, was freed after DNA evidence cleared him of any connection to the crime in suburban Chicago.

Cook County Judge Frank Zelezinski agreed to vacate Abernathy's 1987 conviction following a request from the prosecutor.

"The decision to vacate this conviction comes as a result of a comprehensive investigation by my office into the facts of this case which has revealed evidence that tends to exonerate Christopher Abernathy for the commission of this crime," Cook County State's Attorney Anita Alvarez said in a statement.

Abernathy, who was 18 when he was arrested for Hickey's death, had confessed to the crime. Alvarez's statement said that Abernathy "may have suffered from a diminished mental capacity," and that his signed confession didn't have any significant details about Hickey's slaying.

The statement said recent DNA testing of the available evidence in the case did not match Abernathy's DNA profile.

"This day is more than 10,000 days overdue," Abernathy's mother, Ann Kolus, said, according to the Chicago Tribune.

The newspaper has more on the background of the case:

"On the night of Oct. 3, 1984, Hickey walked to her high school wearing a pink and white dress to perform at a choir concert, according to court records. She was supposed to come home immediately after the concert but never did.

"Her body was found in the bushes near a Marshall Field's store Oct. 5. Her clothes were torn and she had stab wounds to the chest and her throat had been slashed, court records show.

"Abernathy, of Midlothian, was not charged for more than a year after the slaying. Witnesses at trial said Abernathy, who'd dated Hickey, made strange comments at her funeral. One of his friends eventually came forward and told police that Abernathy, who was 17 when the crime was committed, had confessed to him that he killed the girl, according to court records."

Abernathy's attorney, Lauren Kaeseberg, says her client is "just so happy that he's able to go home, that he's free and gets to be with his family."

The case was reviewed by Alvarez's "Conviction Integrity Unit," one of several around the country that have reviewed questionable convictions. Her office will begin a cold-case investigation into the killing, she said.

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