Anyone serving a mandatory sentence of life in prison without parole for a crime they committed as a juvenile has a right to challenge their punishment, the U.S. Supreme Court ruled today. The decision will give roughly 1,000 inmates a shot at reducing their terms, according to NBC News.

In a 2012 case known as Miller v. Alabama, the Court ruled that imposing mandatory life without parole on juvenile offenders constituted a violation of the Eighth Amendment’s ban on cruel and unusual punishment, citing a child’s “diminished culpability and heightened capacity for change.” Today’s decision retroactively applies that thinking to those who were already imprisoned in 2012, giving them an opportunity to argue for a shorter sentence or a parole opportunity.

Many states had already begun retroactively applying Miller, and the ruling will compel the handful of states that have not.“The opportunity for release will be afforded to those who demonstrate the truth of Miller’s central intuition—that children who commit even heinous crimes are capable of change,” Justice Anthony Kennedy wrote in the Court’s majority opinion today.

One inmate who will be unaffected by the change is Making a Murderer’s Brendan Dassey, whose lawyers may currently be experiencing the strange dissonance of wishing he were sentenced more harshly back in 2007. Dassey was a picture of “diminished culpability” when he confessed to killing Teresa Halbach alongside his uncle Steven Avery: sixteen years old, 70 IQ, fourth-grade reading level. However, Dassey’s sentence included the possibility of parole in 2048, excluding him from a review. He will be 59 years old.

Image via AP. Contact the author at andy@gawker.com.