In May The Nation introduced readers to Trina Garnett, serving life without parole in Pennsylvania for a crime she committed in 1976. A severely neglected and abused child with serious mental problems, Trina was 14 when she was arrested for setting a fire that killed two boys on an impoverished block in the Philadelphia suburb of Chester. Represented by a pitifully inadequate attorney who was later disbarred, Trina was convicted and given two sentences of life without parole. The judge, bound by the state’s mandatory sentencing statutes, called the case “one of the saddest I’ve ever seen involving a juvenile.”

On June 25, in Miller v. Alabama, the Supreme Court struck down such punishments, ruling that mandatory sentences of life without parole for juveniles are cruel and unusual, in violation of the Eighth Amendment. In a 5-4 decision written by Justice Elena Kagan, the Court held that “such mandatory penalties, by their nature, preclude a sentencer from taking account of an offender’s age and the wealth of characteristics and circumstances attendant to it.” Such characteristics include the recklessness, immaturity and underdeveloped sense of consequences that common sense suggests—and science confirms—define all teenagers. What’s more, Kagan noted, mandatory sentences leave no room to consider the basic distinguishing features of a given case. “Under these schemes,” she wrote, “every juvenile will receive the same sentence as every other—the 17-year-old and the 14-year-old, the shooter and the accomplice, the child from a stable household and the child from a chaotic and abusive one. And still worse, each juvenile…will receive the same sentence as the vast majority of adults committing similar homicide offenses.”

The decision relied heavily on recent Court precedent. In 2005 Roper v. Simmons banned the death penalty for juveniles based on the vast neurological differences between teens and adults, which render the former less culpable and thus “less deserving of the most severe punishments.” The same logic led the Court in 2010 to forbid life without parole for teens who commit nonhomicide offenses. That ruling, in Graham v. Florida, drew parallels between the death penalty and life without parole, cited by Kagan in Miller. “In part because we viewed this ultimate penalty for juveniles as akin to the death penalty, we treated it similarly…. We imposed a categorical ban on the sentence’s use, in a way unprecedented for a term of imprisonment.”

So why did the Court limit its ruling to mandatory sentences instead of banning juvenile life without parole altogether? One death penalty lawyer described the decision as “incrementalism at its very worst,” pointing out that under Miller, “it would still be OK for a jury to sentence…any 14-year-old to life in prison without the possibility of parole, as long as the jury has the option not to issue that sentence.”

But even as a limited (and split) decision, the ruling is an important rebuke to decades of zero-tolerance reforms that sought ever-harsher punishments for youth. “Adult time” for teens is largely the legacy of criminologists and politicians in the 1980s and ’90s, whose warnings that a new breed of “superpredators” would bring a wave of violent crime were not only false but rooted in racism. While Miller does not note the disproportionate impact this had on minority youth like Trina—race is not mentioned once—it reaffirms the need to treat kids as kids.

The ruling also recognizes that in an age of historically long sentences for violent crimes, at least some people who do terrible things deserve a chance to change. “This mandatory punishment disregards the possibility of rehabilitation even when the circumstances most suggest it,” Kagan wrote, contradicting Justice Antonin Scalia’s glib assertion during oral arguments that “I thought that modern penology has abandoned that rehabilitation thing.”

Finally, for the majority of the 2,589 people serving juvenile life without parole, the ruling’s implications are significant. As Bryan Stevenson, who argued the case before the Court, said following the decision, “Most of the kids that have been sent to life without parole were sentenced in mandatory jurisdictions.” Indeed, in Pennsylvania, which has the largest number of these prisoners, not only are such sentences mandatory for certain crimes; there is no age restriction on when a child can be tried as an adult. Kids as young as 11 have faced the prospect of dying in prison under automatic sentencing rules. Miller should change this. “When you actually give judges and sentencers the discretion to impose a lower sentence involving a juvenile offender,” said Stevenson, “they frequently impose it.”

In the twenty-eight states with mandatory sentencing statutes on the books, prisoners serving juvenile life without parole now have a shot at a new sentence. This will not happen automatically: the onus is on inmates—most of them ill-equipped—to seek a resentencing hearing. As Stevenson points out, “There are a lot of jurisdictions where there is no right to a lawyer for this kind of proceeding.” And even if a prisoner has a chance to make his or her case, there’s no guarantee that he or she will not be given the same punishment—or a similarly harsh one.

For hundreds of others, sentenced under nonmandatory statutes, the future is more uncertain. This includes some 300 inmates in California, where legislative efforts to abolish juvenile life without parole have repeatedly failed. Stevenson is optimistic that even those states will be forced to re-examine their sentencing practices. After Miller, he said, “I think the Eighth Amendment would require that kind of review.”

For now, Stevenson and his organization, the Equal Justice Initiative (EJI), will work to secure counsel for prisoners affected by the ruling, some of whom “have been waiting for decades for the opportunity to have their sentences reconsidered.” While he says “a fair review is much more important than a quick review,” he acknowledges that “it’s difficult, when you feel you’ve been wrongly sentenced, to remain patient.”

In Trina’s case, time is not on her side. Thirty-five years after being locked away, she suffers from multiple sclerosis and can no longer walk. Her family is increasingly concerned about her declining health and the inadequate medical care she gets in prison. But she is fortunate to be represented by EJI lawyer Jacqueline Jones-Peace, who will seek a new sentence, and to have a family eager to welcome her home should she be freed. Reached at her home near Chester hours after the ruling, Trina’s sister Linda was overwhelmed with emotion. She called the decision “a miracle.”

“Words cannot express how we feel right now,” she said. “We are so grateful.” She is particularly grateful to EJI for seeking out her sister and taking her case. And she is grateful to those who read about Trina after all these years. “As children,” Linda said, “we didn’t have a chance to speak out. We didn’t have a chance to tell our story.”