One of America's earliest school shooters wants to get a 'murder review hearing.'

SALEM, Ore. — Twenty-five years after Kip Kinkel murdered his parents, killed two students and wounded 25 others in one of the earliest U.S. high-school shootings, lawyers have filed a new petition with the Oregon Supreme Court.

Kinkel opened fire at Thurston High School in Springfield, Oregon, in May 1998, at a time when America was unaccustomed to seeing such hateful mass violence directed at a school. Historians consider it to be a predecessor of sorts to the oncoming era of mass shootings in the U.S., many of which occur in schools, supermarkets and malls. The Columbine High School massacre occurred about a year later.

The night before the Thurston High School assault, Kinkel killed his parents, William and Faith Kinkel. His classmates, Ben Walker and Mikael Nicholauson, were fatally shot the next day at the school.

Thaddeus Betz, director of the Youth Justice Project and Kinkel's attorney, in April filed the petition asking the state's highest court to grant Kinkel a "murder review hearing."

Such a hearing would determine whether Kinkel is rehabilitated, or is capable of rehabilitation, which could impact how long he remains in prison.

Betz also has taken Kinkel's case to the Ninth Circuit Court of Appeals, arguing Kinkel was "denied the right under the Eight Amendment as interpreted in Miller [v. Alabama] to have his youth appropriately considered before the sentencing court imposed a sentence that guarantees he will die in prison," according to the brief.

"Any time you think about his case, you have to remember that the context of his crime was a 15-year-old undiagnosed schizophrenic who didn't understand what mental illness was," Betz said.

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25 years of legal battles, trauma

Attorneys representing Kinkel, now 40, have spent the past two decades appealing his sentence on the basis of constitutionality and Kinkel's mental health. Several post-conviction petitions and appeals in Oregon since 2002 have been ultimately denied.

Court documents say Kinkel has schizophrenia and "suffers delusions and auditory hallucinations," and hears voices that order him to do things.

His counsel petitioned in 2011 to move him to the state hospital to serve his sentence and receive treatment for mental illness. The petition was dismissed without prejudice, meaning it was denied but could be refiled.

Subsequent petitions have drawn on for years. An appeal filed in 2011 was officially rejected in district court in 2022. It's now in the Ninth Circuit Court of Appeals.

Kinkel has since publicly expressed remorse and told HuffPost in 2021, he feels "tremendous guilt and shame."

After Kinkel's most recent appeal to the Oregon Board of Parole and Post-Prison Supervision was denied, Betz took the case to the state's highest court.

Betz said Kinkel's legal team "wouldn't be asking for the hearing if we didn't think we'd be successful in proving Mr. Kinkel is rehabilitated."

But victims who were injured in the shootings and family members of victims who were killed have said they still carry trauma and have permanent damage.

"I and many other survivors are still dealing with the fallout," Betina Lynn, who was shot and survived, told HuffPost in 2021. "We are all serving life sentences right alongside him."

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Life in prison, no life sentence

Kinkel is serving sentences that will keep him in prison for the rest of his life. He is serving four concurrent 25-year sentences for murder, plus 87 years for attempted murder charges which makes him ineligible for a murder review hearing, the parole board ruled in March.

According to Oregon statue, which was amended a month before Kinkel's sentencing, anyone convicted of murder in the second degree (Kinkel's conviction) who was at least 15 at the time of the crime "shall be punished by imprisonment for life."

After 25 years, however, the state parole board can hold a murder review hearing. If the board decides a person is "likely to be rehabilitated within a reasonable period of time," it can reduce the sentence to life with the possibility of parole or some form of release.

A murder review hearing may alter a life sentence, but Kinkel "is not serving any 'life sentence' for murder," the board wrote in March. The board does not have any authority over sentences related to Kinkel's attempted murder charges.

Betz said the nature of Kinkel's sentences should not bar him from the chance to prove whether he is capable of rehabilitation.

"It seems like a point of information that everybody ought to be aware of," Betz said. "Seems like a good thing for us to know, for many reasons."

The Oregon Supreme Court will decide whether to review Kinkel's petition. The petition to the Ninth Circuit Court of Appeals is being considered for oral argument in Portland between August and December.

Shannon Sollitt is a corps reporter for Report for America, a program that aims to support local journalism and democracy by reporting on under-covered issues and communities. Send tips, questions and comments to ssollitt@statesmanjournal.com

This article originally appeared on USA TODAY NETWORK: Kip Kinkel files petition 25 years after Thurston High School shooting