There is nothing uncommon about laws requiring life without parole for juvenile murderers, so such punishment can hardly be barred by the Eighth Amendment. As Justice Elena Kagan's majority opinion concedes, legislators in 28 states plus the federal government have enacted laws mandating that penalty. Courts have meted it out thousands of times. Liberals may disapprove of mandatory "true life," but it plainly isn't unusual. By definition, therefore, it isn't "cruel and unusual."
Miller marks the third time in recent years that the Supreme Court has invoked "evolving standards of decency" to rationalize a new constitutional barrier to punishing minors convicted of terrible crimes. In Roper v. Simmons 2005), the court outlawed the death penalty for any criminal who was under 18 at the time of his offense. At the time, the majority observed that "life imprisonment without the possibility of parole" would remain an option. Yet now, in what the dissent calls "classic bait and switch," the court tells states they may not insist on that option.
In Graham v. Florida (2010), meanwhile, the court ruled that juvenile offenders could not be sentenced to a lifetime behind bars for any crime but homicide, no matter how violent. (After all, said the court, "there is a line between homicide and other serious violent offenses.") But now five justices declare that mandatory life sentences are unconstitutional for youthful killers too. And it's only a matter of time, they hint broadly, until even discretionary life-without-parole is struck down.
In all these cases, the court has leaned heavily on social science and psychiatry. Since adolescents tend by nature to be more reckless and impulsive than adults, the majority argues, they cannot be assigned quite the same "moral culpability" for their deeds.
As a general rule, that's obvious; it's why the law distinguishes between adults and minors in the first place. But why should policymakers be prohibited from recognizing exceptions to the rule, and treating juveniles as adults in certain extreme circumstances?
Suppose, to go back to that terrible day in 1996, a 17-year-old had burst in on Mangum and prevented him from murdering Janet and Jennifer Davis. If public officials then wished to reward that teen for his life-saving courage, no one would suggest that the honor be diminished on the grounds that the hero's adolescent brain didn't fully grasp the significance of his valiant behavior. Most Americans would regard it as similarly unreasonable to suggest that any juvenile who acts with criminal depravity must be too mentally immature to understand what he is doing.
Supreme Court justices may personally disagree, of course. But to turn their disagreement into a constitutional imperative? To wrap their subjective views in the authority of the Eighth Amendment? That is inexcusable, and Mitt Romney ought to say so.