This is likely Justice Stevens’s last pronouncement on the Death Penalty as a Supreme Court Justice. And he packs a punch, to help cement his legacy.

Society changes. Knowledge accumulates. We learn, sometimes, from our mistakes. Punishments that did not seem cruel and unusual at one time may, in the light of reason and experience, be found cruel and unusual at alater time; unless we are to abandon the moral commit-ment embodied in the Eighth Amendment, proportionality review must never become effectively obsolete, post, at 8–9, and n. 2.

While JUSTICE THOMAS would apparently not rule out adeath sentence for a $50 theft by a 7-year-old, see post, at 4, 10, n. 3, the Court wisely rejects his static approach to the law. Standards of decency have evolved since 1980. They will never stop doing so.

In other words, standards of decency will keep evolving long after I’m gone, and soon the death penatly will be categorically cruel and unusual. KTHXBAI.

Justice Thomas in dissent snaps back.

I agree with JUSTICE STEVENS that “[w]e learn, some-times, from our mistakes.” Ante, at 1 (concurring opinion). Perhaps one day the Court will learn from this one.