Shortly after the U.S. Supreme Court issued its decision in Atkins v. Virginia holding that the execution of mentally retarded persons violated the Eighth Amendment, legal scholars, advocates, and journalists began to speculate that the Court would next turn its attention to the question of the execution of persons who were juveniles – below eighteen years of age – at the time they committed homicide. Following the Atkins decision, four Justices expressed the view that the rationale of Atkins also supported the conclusion that execution of juvenile offenders was unconstitutional. A constitutional test of capital punishment for juveniles was inevitable.
The Atkins Court held that capital punishment was an unconstitutionally cruel and unusual punishment for the mentally retarded for two reasons. First, the Court concluded that the impairments associated with mental retardation both reduced the culpability of the mentally retarded, making death a disproportionate punishment for them, and created a "special risk of wrongful execution." Second, the Court found that a national consensus had emerged that death is an excessive punishment for the mentally retarded.
As evidence of that national consensus, the Court pointed to the growing number of states that expressly barred the imposition of the death penalty on the mentally retarded: since 1989, when the Court had last considered the constitutionality of executing the mentally retarded, the number of states with such legislation had grown from two to eighteen. In addition, the Court observed that, even in states where the death penalty was theoretically a permissible punishment for the mentally retarded, it was rarely imposed: since 1989, only five states had executed offenders known to be mentally retarded.
Like the question of execution of the mentally retarded, the question of the constitutionality of the death penalty for juveniles was last visited by the Supreme Court in 1989. That year, in Stanford v. Kentucky, the Court concluded that the death penalty was not inherently disproportionate to the culpability of adolescents and that individualized assessments could reliably sort out which juveniles were sufficiently morally culpable. And it held that no national consensus barred the imposition of capital punishment on sixteen- or seventeen-year-old juveniles.
The Decline of the Juvenile Death Penalty: Scientific Evidence of Evolving Norms,
J. Crim. L. & Criminology
Available at: https://scholarship.law.columbia.edu/faculty_scholarship/586