The U.S. Supreme Court's new conservative majority made a U-turn on Thursday, ruling by a 6-3 vote, that a judge need not make a finding of "permanent incorrigibility" before sentencing a juvenile offender to life without parole.

It was the first time in almost two decades that the high court has deviated from rules establishing more leniency for juvenile offenders, even those convicted of murder.

At the center of the case was Brett Jones, now 31, who was 15 when he stabbed his grandfather to death during a fight about Jones' girlfriend. He was convicted of murder, and a judge sentenced him to life without parole.

"In such a case, a discretionary sentencing system is both constitutionally necessary and constitutionally sufficient," the court's conservative justices wrote.

Writing for the majority, Justice Brett Kavanaugh said: "As this case again demonstrates, any homicide, and particularly a homicide committed by an individual under 18, is a horrific tragedy for all involved and for all affected."

He added: "Determining the proper sentence in such a case raises profound questions of morality and social policy. The States, not the federal courts, make those broad moral and policy judgments in the first instance when enacting their sentencing laws. And state sentencing judges and juries then determine the proper sentence in individual cases in light of the facts and circumstances of the offense, and the background of the offender."

Over the past two decades, the law on juvenile sentencing has changed significantly. The Supreme Court — primed by research that shows the brains of juveniles are not fully developed, and that they are likely to lack impulse control — has issued a half dozen opinions holding that juveniles are less culpable than adults for their acts. And the court has also ruled that some of the harshest punishments for acts committed by children are unconstitutionally cruel and unusual punishment.

After striking down the death penalty for juvenile offenders, the court, in a series of decisions, limited life without parole sentences to the rarest cases — those juvenile offenders convicted of murder who are so incorrigible that there is no hope for their rehabilitation.

But all of those decisions were issued when the makeup of the court was quite different than it is now. This case was the first time the court has heard arguments in a juvenile sentencing case with three Trump appointees on the bench, including new Justice Amy Coney Barrett, who replaced the late Justice Ruth Bader Ginsburg.

Previously, Justice Anthony Kennedy, who retired in 2018, repeatedly was the deciding vote in cases involving life sentences and other harsh punishments for juvenile offenders. But with Kennedy retired and replaced by Kavanaugh, and with Ginsburg replaced by Barrett, the court in this case indicated that it is not inclined to go the extra mile to protect juvenile offenders from the harshest punishments.

"It's like the wind was blowing one way and now it's blowing in the opposite direction," says Donald Ayer, a former prosecutor and deputy attorney general in Republican administrations. He and other former prosecutors and judges, including two former Republican U.S. Attorneys General, filed a brief siding with Jones in this case.

Jones was originally sentenced to life without parole in 2004, but when the Supreme Court ruled that those, like Jones, who committed crimes when they were minors could not be automatically sentenced to life terms, he had to be resentenced. By then, he had spent a decade in prison, had graduated from high school, and earned a record as a model prisoner.

At his resentencing hearing, the judge did consider Jones' youth at the time of the crime, but again sentenced him to life without parole. The judge did not make any finding that Jones was so incorrigible that he had no hope of rehabilitation.

Jones' lawyer appealed all the way to the U.S. Supreme Court, contending that consideration of a defendant's youth is not enough and that Jones, now in his 30s, should have at least a chance at parole because he has shown he is capable of rehabilitation.

Twenty-five states ban life without parole for juveniles entirely. And six more states do not have anyone serving that sentence for a crime committed when a juvenile. But 19 states do allow life without parole for juvenile murderers.

In a withering dissent Thursday, Justice Sonia Sotomayor used language from Justice Kavanaugh's past opinions to write that the court's decision was "an abrupt break from precedent." She accused he majority of using "contortions" and "distortions" to "circumvent" legal precedent. The majority, she said, "is fooling no one."

The court's previous rulings, she wrote, require that most children be spared from punishments that give "no chance for fulfillment outside prison walls" and "no hope." She quoted Jones as saying at his resentencing hearing, "I've pretty much taken every avenue that I could possibly take ... to rehabilitate myself ... I can't change what I've done. I can just try to show ... I've become a grown man."

Thursday's ruling will certainly make it more difficult for juvenile offenders like Jones to show judges they deserve another chance at freedom somewhere down the road, says Cardozo Law School's Kathryn Miller. "It's going to be much harder to convince judges" that evidence of rehabilitation is relevant, she says.

"A lot of times these judges really want to still focus on the facts of the crime" even though it is years or decades later, she said. "They're not interested in the rehabilitation narrative."

Neither, it seems, is the newly constituted conservative Supreme Court majority.

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