The Supreme Court moved the nation’s justice system forward in 2012 by ruling that mandatory life sentences for juveniles violated the Eighth Amendment ban on cruel and unusual punishment. That, however, did not determine whether the ban on such sentences should apply retroactively to 2,000 juvenile lifers nationwide.

Juveniles are far more impulsive than adults and less equipped to grasp the consequences of their actions. Moreover, no judge or jury can predict what a 15-year-old convicted of murder will become at 35, 45 or 55.

The arguments for retroactivity are compelling. If mandatory life sentences for juveniles are considered unconstitutionally cruel, then fairness requires states to right the wrongs of the past. At issue is not whether states can impose a life sentence on a juvenile, but whether such sentences can be mandatory. Life-without-parole remains permissible for juveniles, but only after individual circumstances, including prospects for change and reform, are taken into account.

Opponents of retroactivity argue that such considerations and inquiry are too difficult, years or decades after the crime. On the contrary, a person’s ability to change – based on experience, not psychological conjecture – should become clearer years or decades later.

Making the Supreme Court’s ban on mandatory life sentences retroactive would not, in itself, release a single prisoner. It would only make those who were serving such sentences before 2012 eligible for resentencing or parole.

In deciding the issue of retroactivity for all states, justices will hear an appeal this term from George Toca, who at 17 fatally shot a friend during a botched robbery in 1984 in Louisiana. By agreeing to hear arguments, the Supreme Court can take another step toward a more rational, humane and effective justice system.