Updated at 9:35 p.m.

A man convicted in the 1989 killing of the Oregon Department of Corrections director should be retried or released from prison because evidence was excluded from his trial that pointed to someone else as the possible killer, a federal judge ruled Thursday.

Frank Gable’s attorneys during his 1991 Marion County Circuit Court trial also didn’t adequately help him assert his due process rights in light of the error, according to an opinion and order written by U.S. Magistrate Judge John V. Acosta.

Gable, 59, was found guilty of aggravated murder and murder in the January 1989 stabbing of Michael Francke, 42, in Salem and has been serving a life sentence without parole since his conviction.

It’s not immediately clear Thursday if Marion County prosecutors plan to retry Gable. Acosta said prosecutors should make a decision within 90 days of his order.

[Read the judge’s opinion and order]

Gable has appealed his conviction several times, taking his contentions to the Oregon Court of Appeals and Oregon Supreme Court, but failed to get the ruling overturned. Acosta’s ruling comes after he heard arguments in 2016 by federal public defenders and state lawyers on Gable’s petition for a new trial or parole.

The federal public defender’s office filed a brief in 2014 saying the prosecution of Gable was flawed and that about half a dozen witnesses had recanted statements directly linking Gable to Francke’s death. The Oregon Innocence Project has also filed a brief on Gable’s behalf raising questions about the case.

Federal public defenders also argued that John Crouse, a Salem man who was on parole for a robbery at the time, repeatedly confessed to killing Francke, telling numerous law enforcement officers as well as his own mother, brother and girlfriend that he stabbed Francke when he caught Crouse burglarizing his car on Jan. 17, 1989.

Crouse’s confession, they said, matched the crime scene and autopsy evidence, corroborated by eyewitness testimony and considered truthful by an FBI polygrapher.

The federal defenders argued that the trial court that convicted Gable improperly excluded Crouse's earlier confession to the crime.

The Oregon Department of Corrections said in a statement late Thursday that “our hearts go out to Michael Francke’s family.”

"We do not have many details as to next steps and we are working with the Department of Justice and other partners to determine what those steps may be," the statement said.

The agency declined to say where Gable is incarcerated. He has long been in prison out of state.

Michael Francke's brothers, Kevin and Patrick, have long maintained that Gable is innocent. After Thursday's ruling was handed down, Patrick Francke posted an excerpt of the judge's ruling on Facebook. "My brother and I have been working toward this day for almost 30 years," he wrote.

Francke was found dead by a security guard Jan. 17, 1989 on a covered porch on the Oregon State Hospital grounds in Salem. Gable, then in his early 30s, was indicted in the killing by a Marion County grand jury in April 1990.

Marion County prosecutors argued that Francke came upon Gable as Gable was breaking into the state prison system director’s car. They said Gable stabbed Francke three times and then fled. Francke staggered to the porch and died.

Gable’s attorneys at the time pointed to a lack of physical evidence tying Gable to the killing and suggested other people could have been involved in the death.

Police began speaking to Gable about the killing four months later after receiving a tip. Gable was interviewed by detectives several times and was accused in Francke’s death in April 1990.

Associates of Gable offered testimony against Gable, including that they saw him drive away from the state hospital grounds around the time Francke was stabbed, that Gable asked to get rid of a plastic bag with unknown items inside, and that Gable alluded to doing something that would make the news.

Gable’s wife at the time, who worked at the state hospital, testified that Gable often carried knives.

Gable’s trial lasted four months and ended in him being found guilty of aggravated murder and murder. He was sentenced to life in prison without parole in July 1991. During a court break in the trial, Gable married an attorney who represented him on an unrelated federal gun charge. They divorced in 1997.

Federal public defenders said seven witnesses in Gable’s murder case, two of whom initially said they saw Gable stab Francke, and five others who claimed Gable confessed to killing the prison official, later recanted their accounts. They said they felt forced, coerced or intimidated by police investigators into giving false or misleading statements related to the death, according to the federal judge’s order.

Noelle Crombie of The Oregonian/OregonLive staff contributed to this report.

-- Everton Bailey Jr.

ebailey@oregonian.com | 503-221-8343 |@EvertonBailey

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