NEW ORLEANS (AP) — A Louisiana parole board granted parole on Wednesday to Henry Montgomery, whose Supreme Court case was instrumental in extending the possibility of freedom to hundreds of people sentenced to life in prison without the opportunity for parole when they were juveniles.

Montgomery, 75, was convicted in the 1963 killing of East Baton Rouge sheriff’s deputy Charles Hurt, who caught him skipping school. Montgomery was 17 at the time. He was initially sentenced to death but the state’s Supreme Court threw out his conviction in 1966, saying he didn’t get a fair trial. The case was retried, Montgomery convicted again but this time sentenced to life in prison without the possibility of parole. He served decades at the Louisiana State Penitentiary at Angola.

In 2012, the Supreme Court ruled in Miller v. Alabama that mandatory sentencing of life without parole for juvenile offenders was “cruel and unusual” punishment. But it didn’t settle the question of whether that decision applied retroactively or only to cases going forward.

In 2016, the Supreme Court settled the matter when it took up Montgomery’s case and extended their decision on such sentences to people already in prison.

The decision ushered in a wave of new sentences and the release of inmates from Michigan to Pennsylvania, Arkansas and beyond. Since the court’s Montgomery decision, about 800 people who had been sentenced to life without parole as juveniles have been released, according to the Campaign for the Fair Sentencing of Youth.

Montgomery was resentenced to life with parole and the state judge who resentenced Montgomery called him a “model prisoner” who appears to be rehabilitated. But that didn’t translate into immediate freedom. The parole board twice previously rejected his application. The last time he was rejected for parole was in 2019.

Montgomery will be released into the care of the Louisiana Parole Project which was created in 2016 by a former juvenile lifer to assist people who have served long prison sentences — generally 20 years or more — reenter society. The organization helps former inmates with housing, signing up for health care or medications, getting an ID card and learning how to navigate society.

Hurt, the sheriff’s deputy who Montgomery killed, was married and had three children. Two of his daughters have met with Montgomery in prison and forgiven him, but family members have opposed his release.