The two categorical exclusions of age and mental capacity will impact not only those offenders who are excluded from the death penalty, but also those offenders who remain subject to this punishment. The Supreme Court’s decisions in Roper v. Simmons and Atkins v. Virginia raise the issue that a capital-punishment-limiting decision possesses wrongs of its own. Both decisions limit the death penalty—Roper excludes from this punishment offenders who committed their crimes before they were eighteen years old and Atkins excludes offenders who are mentally retarded. But in both cases, the Supreme Court overstated the uniformity and universality of traits associated with diminished culpability among juvenile and mentally retarded offenders. Contrary to that impression, not all offenders who are excluded from the death penalty under Atkins and Roper are necessarily less culpable than are offenders who remain subject to this punishment.

Categorical exclusions such as age and culpability might solve the problem of improperly sentenced mentally retarded or juvenile offenders, but they raise other problems. The Roper Court failed to consider those problems, and the Atkins Court could not possibly have considered those problems because accepting the Court's reasoning requires denying that these problems even exist. Although the many wrongs of capital punishment provide strong motivation for believing that the Atkins and Roper decisions are right, the rightness of these decisions becomes far from certain when the consequences for non-excluded offenders are considered. Capital punishment after Atkins and Roper might appear to be more just, but this appearance is misleading.