The Michigan appeals court heard arguments in a case that could determine whether prisoners locked up for murder when they were teens will be given a shot at parole.

The issue is whether a recent U.S. Supreme Court decision should apply retroactively to more than 350 people serving mandatory life sentences with no chance of parole. The Supreme Court says that such punishments for minors are unconstitutional.

Among those cases is Dakota Eliason’s. Elisason was only 14 when he murdered his sleeping grandfather. His lawyer appealed the sentence of life without parole, saying that it constituted cruel and unusual punishment. Eliason’s case is still pending, so he will be resentenced under the new rule.

Another inmate whose sentence may be reconsidered is Efren Paredes Jr. For the past 24 years Paredes has served his sentence of life without parole. He was convicted in 1989 for the murder of Rick Tetzlaff, but has maintained his innocence over the duration of his time in prison. It will now be up to a judge to decide whether to uphold the life sentences or lessen them.

Attorney General Bill Schuette says the appeals court’s ruling should not benefit people already in prison. The state appeals court heard arguments Tuesday in the case of a St. Clair County man, Raymond Carp, who was convicted of murder committed when he was 15.

The judges presiding over this decision are William Whitbeck, Michael Talbot and E. Thomas Fitzgerald.

Separately, a federal judge in Ann Arbor is handling a similar case. His decision could trump what happens in state court.