A federal judge says Oregon must release Frank Gable, the man convicted in the 1989 killing of the head of the state Department of Corrections.

In vacating Gable’s conviction, U.S. Magistrate Judge John Acosta ruled Thursday that the state should free Gable within 90 days unless prosecutors opt to retry him.

“Although the evidence presented at trial in 1991 resulted in a guilty verdict, the court concludes that it is more likely than not that no reasonable juror would find Gable guilty in light of the totality of all of the evidence uncovered since that time,” Acosta wrote, “particularly the newly presented evidence of witness recantations.”

A spokeswoman for the Oregon Department of Justice said late Thursday that the agency was still reviewing the decision and evaluating its options. Attorney General Ellen Rosenblum will not be involved in determining whether to appeal the case because she  served on the Oregon Court of Appeals during the time Gable was appealing his conviction.

Lisa Hay, whose federal public defender office represented Gable in his habeas corpus petition, said the ruling is an exoneration.

“No one has an interest in keeping an innocent man in prison,” Hay said. “He’s struggled being in custody, but this case now brings him justice.”

Gable has been behind bars for three decades. Hay said he’s always maintained his innocence.

Gable’s original conviction was highly controversial. Prosecutors never found DNA evidence tying him to the scene of the murder. More recently, the Oregon Innocence Project studied the case at the request of Gable’s lawyers and questioned how evidence and potential witnesses were handled.

“There’s no physical evidence to convict our client; there were just inconsistent statements by supposed eyewitnesses. At the end, most of the trial witnesses later admitted they lied at the trial and there are concerns about the coercive and improper interrogation techniques that were used,” Hay said. “No one should have confidence in this 1991 verdict.”

Acosta ruled that the original judge should have allowed evidence that pointed to another potential killer who confessed and has since died. He faulted Gable’s original attorneys for not following up on mistakes made by the court.