(AREA) -- A Michigan Supreme Court decision won't be the last word about whether hundreds of inmates serving no-parole sentence can get out of prison. Judges now have more options when they sentence anyone convicted of murder under age 18, including a no-parole punishment. But the court on Tuesday refused to apply the new legal standard to prisoners already behind bars. The controversy isn't over. Separately, an Ann Arbor federal judge last year ordered parole hearings for more than 300 prisoners. That remedy is on hold while Attorney General Bill Schuette appeals. Schuette opposes any new benefit for prisoners who have exhausted appeals of no-parole sentences. His office in the past filed a 29-page brief in the Michigan appeals court in the case of a St. Clair County man, Raymond Carp. He was 15 when he was involved in the brutal death of a woman in 2006. The Legislature could change Michigan law to help juvenile lifers. But the chairman of the House Criminal Justice Committee says there's no support this year.