Sandra Day O'Connor

“ The special qualitative characteristics of juveniles that justify legislatures in treating them differently from adults for many other purposes are also relevant to Eighth Amendment proportionality analysis. These characteristics, however, vary widely among different individuals of the same age, and I would not substitute our inevitably subjective judgment about the best age at which to draw a line in the capital punishment context for the judgments of the Nation's legislatures. ”

“ In New Jersey, which now permits some 14-year-olds to be tried as adults, the minimum age for capital punishment is 18. In both cases, therefore, the decisions to lower the age at which some juveniles may be treated as adults must have been based on reasons quite separate from the legislatures' views about the minimum age at which a crime should render a juvenile eligible for the death penalty. ”

“ The narrow conclusion I have reached in this case is consistent with the underlying rationale for that principle, which was articulated many years ago by Justice Jackson: "We are not final because we are infallible, but we are infallible only because we are final." ”

“ In previous cases, we have examined execution statistics, as well as data about jury determinations, in an effort to discern whether the application of capital punishment to certain classes of defendants has been so aberrational that it can be considered unacceptable in our society. ”

“ The restrictions that we have required under the Eighth Amendment affect both legislatures and the sentencing authorities responsible for decisions in individual cases. Neither automatic death sentences for certain crimes, for example, nor statutes committing the sentencing decision to the unguided discretion of judges or juries, have been upheld. ”

“ Whatever other implications the ratification of Article 68 of the Geneva Convention may have, and whatever effects the Senate's recent action may eventually have, both tend to undercut any assumption that the Comprehensive Crime Control Act signals a decision by Congress to authorize the death penalty for some 15-year-old felons. ”

“ Legislatures recognize the relative immaturity of adolescents, and we have often permitted them to define age-based classes that take account of this qualitative difference between juveniles and adults. ”

“ The very real possibility that this result was not considered is illustrated by the recent federal legislation, cited by the dissent, which lowers to 15 the age at which a defendant may be tried as an adult. See post, at 865 (discussing Comprehensive Crime Control Act of 1984, Pub. L. 98-473, 98 Stat. 2149) . Because a number of federal statutes have long provided for capital punishment, see post, at 866, n. 1, this legislation appears to imply that 15-year-olds may now be rendered death eligible under federal law. ”