In Kennedy v. Louisiana, the United States Supreme Court held unconstitutional a state law that provided for the imposition of death upon one convicted of raping, but not killing or attempting to kill, a child. Justice Anthony Kennedy wrote the opinion for the Court, in which the majority, employing various analytical tools, brought its “own judgment” to bear on the excessiveness, and therefore the constitutionality, of the death sentence under the Eighth Amendment’s Cruel and Unusual Punishments Clause. In emphasizing the Court’s use of its own judgment in making the determination of excessiveness or disproportionality, Justice Kennedy and the majority risked the same public and internal, dissenting Court criticisms that accompanied previous death penalty opinions in which Court majorities and pluralities similarly employed their own judgments. In the sharp divide over these issues, critics have accused those jurists of disguising their personal views of morality as the doctrinal application of their “own judgment” on these questions. This article argues that despite the criticisms, and despite the Court’s statement that at least some of its capital punishment case law is “still in search of a unifying principle,” there is a precedential thread unifying and justifying the Court’s own assessment of excessiveness under the Eighth Amendment. Historical analysis of the Court’s Eighth Amendment statements shows that the clear thread in the cases is respect for human dignity and restraint that plays out through the Amendment’s proportionality guarantee. The Court’s application of that guarantee against excessiveness has time and again invoked the Court’s own judgment, based on contemporary knowledge of punishment, of punishment’s goals, and about decency in punishment. The article argues that approach is the sound and historical one and that the Court should continue to apply its own judgment about decency, excessiveness, and proportionality, despite criticisms from the Court’s conservative members about personal predilections.