This Supreme Court term marks a crossroads for death penalty jurisprudence. For the first time since 1890, the Court is considering the constitutionality of a particular means of execution--the lethal injection cocktail currently used by most states. And it is expected to rule, in a second case, on the constitutionality of capital punishment for a crime other than murder--the rape of a child. Both cases require the Court to construe one of the most nebulous clauses of the Constitution, the Eighth Amendment's ban on "cruel and unusual punishments," as well as the controversial 2005 precedent, Roper v. Simmons.

In that case, the Court considered an appeal from Christopher Simmons, sentenced to death by a Missouri jury for abducting 46-year-old Shirley Crook from her home, wrapping her head in duct tape, hog-tying her with electrical wire, and throwing her off of a bridge to drown. The Supreme Court held that 17-year-old Simmons's sentence violated the Eighth Amendment. Writing for the majority, Justice Anthony Kennedy cited "the overwhelming weight of international opinion against the juvenile death penalty" and concluded that "the express affirmation of certain fundamental rights by other nations and peoples simply underscores the centrality of those same rights within our own heritage of freedom."

Two aspects of the ruling in Roper v. Simmons sparked contention: its dubious conclusion that Simmons--who had bragged to his friends that he could "get away with it" because he was a minor--had "a greater claim than adults to be forgiven for failing to escape negative influences," and the Court's use of foreign law to help tease this conclusion from the language of the U.S. Constitution.

The composition of the Court has significantly changed since Roper--in particular with the retirement of Sandra Day O'Connor (who has subsequently stressed the importance of relying on international and foreign courts in examining domestic issues to "create that all-important good impression" abroad). Yet all five justices forming the Roper majority remain on the Court, and this term's death penalty cases--Baze v. Rees, argued in January, and Kennedy v. Louisiana, due to be heard in April--could yield a deeper entrenchment of foreign mores as constitutional arbiters of punishment under our laws. Either way, the Court could dramatically redefine the Eighth Amendment limitations on both the scope and nature of the death penalty.

Over the years, the vagueness of the words "cruel" and "unusual" has spawned a uniquely amorphous line of precedent. In 1958 the Supreme Court held that the Eighth Amendment must draw its meaning "from the evolving standards of decency that mark the progress of a maturing society," thus charging judges with interpreting the world around them to find the meaning of the constitutional text. In 1976 the Court added that use of the death penalty must contribute to the "acceptable goals of punishment"--which it later defined as retribution against a criminal and deterrence of future crimes--and must not be "grossly out of proportion to the severity of the crime." The second criterion has left the law somewhat unsettled as to whether a crime other than murder can ever be punished by death.