THE U.S. Supreme Court recently banned mandatory life sentences for juveniles, a smart ruling that ought to shift public attitudes away from viewing young people who commit terrible crimes as always being beyond redemption.

Compelling research on adolescent brain development argues that a lack of maturity is a key factor for young offenders. A convicted murderer at age 15 may be a redeemable citizen by 40.

Before the court's ruling, the potential for rehabilitation had been lost in the 29 states — including Washington — with mandatory-life-in-prison laws for juvenile offenders. The court ruled 5-4 that such laws violate the Eighth Amendment protection against cruel and unusual punishment.

A return to judicial flexibility and discretion is welcome.

Life in prison without parole should not be an automatic sentence. Judges ought to be able to craft the most appropriate punishment for the harshest crimes. For the most heinous murders, judges may still hand down life sentences without a chance of parole but the decision would be the judge's and not a blind application of state law.

This could be a game-changer for 26 juveniles in Washington state. Their cases may be reheard.

Even so, prosecutors have a point in hoping judges use their discretion and ability to weigh egregious facts to keep some killers in prison for the rest of their lives.

For example, Jeremiah Bourgeois was 14 when he killed the owner of a West Seattle convenience store who had testified against his older brother in a robbery trial. The high court ruling is not expected to lead to the release of Alex Baranyi, who as a 17-year-old in 1997 teamed up with his best friend and bludgeoned to death four members of his Bellevue family.

Across the nation, 2,500 juveniles facing a lifetime in prison can have their sentences re-evaluated. Age at the commission of the crime will be one of the things the new ruling will allow the judges to consider.

Justice is about crime and punishment but also redemption. That's the essence of the court's ruling.