'The operation was a success, but the patient died.' What such a procedure is to medicine, the Court's opinion in this case is to law. - Antonin Scalia

As Justice Stevens explains, “ ‘objective evidence, though of great importance, [does] not wholly determine the controversy, for the Constitution contemplates that in the end our own judgment will be brought to bear on the question of the acceptability of the death penalty under the Eighth Amendment.’ ” (quoting Atkins v. Virginia). “I have relied on my own experience in reaching the conclusion that the imposition of the death penalty” Purer expression cannot be found of the principle of rule by judicial fiat. In the face of Justice Stevens’ experience, the experience of all others is, it appears, of little consequence. The experience of the state legislatures and the Congress—who retain the death penalty as a form of punishment—is dismissed as “the product of habit and inattention rather than an acceptable deliberative process.” The experience of social scientists whose studies indicate that the death penalty deters crime is relegated to a footnote. The experience of fellow citizens who support the death penalty is described, with only the most thinly veiled condemnation, as stemming from a “thirst for vengeance.” It is Justice Stevens’ experience that reigns over all.

It is one of the unhappy incidents of the federal system that a self-righteous Supreme Court, acting on its Members' personal view of what would make a 'more perfect Union' (a criterion only slightly more restrictive than a 'more perfect world') can impose its own favored social and economic dispositions nationwide.

What today's decision will stand for, whether the Justices can bring themselves to say it or not, is the power of the Supreme Court to write a prophylactic, extraconstitutional Constitution, binding on Congress and the States.