(The Root) -- It may have been overshadowed by other news from the Supreme Court, but on Monday the nine justices also handed down a major juvenile-justice ruling.

The court ruled 5-4 that mandatory life-without-parole sentences for juvenile offenders, ages 17 and under, are unconstitutional. The decision expanded a 2010 Supreme Court decision, which had declared such sentences cruel and unusual punishment for teens whose crimes did not involve homicide. Now, in cases of homicide, too, states cannot impose mandatory life-without-parole sentences on juveniles, striking down statutes in 29 states that allow it.

The decision was based on the consolidated cases of Kuntrell Jackson and Evan Miller, who were both given life-in-prison sentences with no chance of parole for their involvement in homicides when they were 14 years old. In essence the majority argued that children are not adults corrupted beyond redemption, but unformed people with the capacity to change and grow.

The ruling does not automatically free any of the estimated 2,000 prisoners serving life sentences for crimes committed as juveniles (60 percent of whom are black); nor does it forbid such life terms for youths convicted of homicide. Rather, sentencing judges must first take into account the offender's age, the nature of the crime and other mitigating factors.

Bryan Stevenson, the executive director of the Equal Justice Initiative, who represented Jackson and Miller before the Supreme Court, spoke with The Root about his commitment to juvenile offenders and why he believes that mandates locking them up for life without parole are unconstitutional.

The Root: With regard to the people serving mandatory life sentences for homicide convictions when they were teens, what will happen to them now?

Bryan Stevenson: They will now be entitled to new sentencing hearings. I think it's significant that the court went on to say that cases where life without parole will be reinstated are expected to be "uncommon." What they've said about the difficulty of making permanent judgments about kids makes this a sentence that we should not see in a lot of cases.

I actually think a lot of these folks will be advantaged by showing institutional histories that suggest that they are not beyond hope, redemption or rehabilitation. A lot of our clients have done really well and have accomplished some pretty impressive things, given that they've been told they're going to die in prison. That may be influential at these resentencings.

TR: What about youths serving life-without-parole sentences that were not subjected to mandatory-sentencing guidelines? Does the ruling impact them at all?

BS: I think it does. The court seems to be requiring that sentencing judges give full weight and consideration to child status before imposing a life-without-parole sentence. Even in many of the nonmandatory cases, that didn't happen. I expect to see challenges and appeals in those cases, which may result in new sentencings.

TR: In his dissenting opinion, Chief Justice John Roberts wrote that mandatory life-without-parole sentences for juveniles "could not plausibly be described" as unusual when a majority of states endorse them. To those who believe that this is a fair punishment for teenage homicide offenders, how do you explain that it's cruel and unusual?

BS: I think the chief justice is not properly characterizing the legislative structure of these cases. Most states have never expressly authorized life without parole for juveniles. They've expressly authorized mandatory life without parole for adults, typically repeat offending adults -- the worst of the worst. They have simultaneously thrown more kids into the adult system by lowering the minimum age for trying children as adults. In some states it's as low as 8. So I don't think it's reasonable to say that legislatures have said, "Yes, we want mandatory life-without-parole sentences for 8-year-olds."

It's the confluence of two distinct legislative judgments that has produced this reality. When states passed mandatory life-without-parole sentences, they weren't thinking about 12-year-olds; they were thinking about adult offenders, repeat offenders. That's why I don't think that this issue reflects some repudiation of legislative will that the court sometimes has to deal with.

TR: And the cruel part?

BS: The United States is the only country in the world that condemns children to die in prison. We protect children in virtually every area of the law. We don't let them drink, we don't let them drive or drop out of school until they reach a certain age. We don't allow them to do a lot of things that we allow adults to do because we recognize that they're still forming. The only area where we don't protect children, or recognize child status, is the criminal-justice system.

To recognize the importance of shielding and helping children in every area of the law except when it comes to punishing them is pretty misguided. I don't think it's appropriate to say to any child that they're fit only to die in prison. To me it is cruel to say that.

TR: Why have you made it your life's work to represent juvenile offenders, particularly ones who have committed violent crimes?

BS: I try to define my work around excessive punishment. We are all more than our worst acts. I don't believe people who lie are just liars, or people who steal are just thieves or even people who kill are just killers. I'm the beneficiary of a lot of mercy and compassion, and I think that I, and the larger community, owe that to others who fall.

I also think that if we're going to be a just and fair society, the place where we test our commitment to the rule of law and human dignity is not in how we treat the gifted kids, the privileged kids, the talented kids, but really in how we treat the kids that are broken, that have failed and struggled and been condemned.

Cynthia Gordy is The Root's senior political correspondent.

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