Juveniles are a protected class under the eighth amendment

Excessive bail shall not be required, nor excessive fines imposed, nor cruel and unusual punishments inflicted.

The Court’s conclusion that execution of juveniles constitutes cruel and unusual punishment evolved in much the same manner. Initially, a closely divided Court invalidated one statutory scheme that permitted capital punishment to be imposed for crimes committed before age 16, but upheld other statutes authorizing capital punishment for crimes committed by 16- and 17-year-olds. Important to resolution of the first case was the fact that Oklahoma set no minimum age for capital punishment, but by separate provision allowed juveniles to be treated as adults for some purposes.1 Footnote
Thompson v. Oklahoma, 487 U.S. 815 (1988) . Although four Justices favored a flat ruling that the Eighth Amendment barred the execution of anyone younger than 16 at the time of his offense, concurring Justice O’Connor found Oklahoma’s scheme defective as not having necessarily resulted from the special care and deliberation that must attend decisions to impose the death penalty. The following year Justice O’Connor again provided the decisive vote when the Court in Stanford v. Kentucky held that the Eighth Amendment does not categorically prohibit imposition of the death penalty for individuals who commit crimes at age 16 or 17. Like Oklahoma, neither Kentucky nor Missouri2 Footnote
Wilkins v. Missouri was decided along with Stanford . directly specified a minimum age for the death penalty. To Justice O’Connor, however, the critical difference was that there clearly was no national consensus forbidding imposition of capital punishment on 16- or 17-year-old murderers, whereas there was such a consensus against execution of 15-year-olds.3 Footnote
Compare Thompson , 487 U.S. at 849 (O’Connor, J., concurring) (two-thirds of all state legislatures had concluded that no one should be executed for a crime committed at age 15, and no state had “unequivocally endorsed” a lower age limit) with Stanford , 492 U.S. at 370 (15 of 37 states permitting capital punishment decline to impose it on 16-year-old offenders; 12 decline to impose it on 17-year-old offenders).

Although the Court in Atkins v. Virginia contrasted the national consensus said to have developed against executing persons with intellectual disabilities with what it saw as a lack of consensus regarding execution of juvenile offenders over age 15,4 Footnote
536 U.S. at 314, n.18 . less than three years later the Court held that such a consensus had developed. The Court’s decision in Roper v. Simmons 5 Footnote
543 U.S. 551 (2005) . The case was decided by 5-4 vote. Justice Kennedy wrote the Court’s opinion, and was joined by Justices Stevens, Souter, Ginsburg, and Breyer. Justice O’Connor, who had joined the Court’s 6-3 majority in Atkins , wrote a dissenting opinion, as did Justice Scalia, who was joined by Chief Justice Rehnquist and Justice Thomas. drew parallels with Atkins . A consensus had developed, the Court held, against the execution of juveniles who were age 16 or 17 when they committed their crimes. Since Stanford , five states had eliminated authority for executing juveniles, and no states that formerly prohibited it had reinstated the authority. In all, 30 states prohibited execution of juveniles: 12 that prohibited the death penalty altogether, and 18 that excluded juveniles from its reach. This meant that 20 states did not prohibit execution of juveniles, but the Court noted that only five of these states had actually executed juveniles since Stanford , and only three had done so in the 10 years immediately preceding Roper . Although the pace of change was slower than had been the case with execution of persons with intellectual disabilities, the consistent direction of change toward abolition was deemed more important.6 Footnote
Dissenting in Roper , Justice O’Connor disputed the consistency of the trend, pointing out that since Stanford two states had passed laws reaffirming the permissibility of executing 16- and 17-year-old offenders. 543 U.S. at 596 .

As in Atkins , the Court in Roper relied on its “own independent judgment” in addition to its finding of consensus among the states.7 Footnote
543 U.S. at 564 . The Stanford Court had been split over the appropriate scope of inquiry in cruel and unusual punishment cases. Justice Scalia’s plurality would have focused almost exclusively on an assessment of what the state legislatures and Congress have done in setting an age limit for application of capital punishment. 492 U.S. at 377 ( “A revised national consensus so broad, so clear and so enduring as to justify a permanent prohibition upon all units of democratic government must appear in the operative acts (laws and the application of laws) that the people have approved.” ). The Stanford dissenters would have broadened this inquiry with a proportionality review that considers the defendant’s culpability as one aspect of the gravity of the offense, that considers age as one indicator of culpability, and that looks to other statutory age classifications to arrive at a conclusion about the level of maturity and responsibility that society expects of juveniles. 492 U.S. at 394–96 . The Atkins majority adopted the approach of the Stanford dissenters, conducting a proportionality review that brought their own “evaluation” into play along with their analysis of consensus on the issue of executing persons with intellectual disabilities. Three general differences between juveniles and adults make juveniles less morally culpable for their actions. Because juveniles lack maturity and have an underdeveloped sense of responsibility, they often engage in “impetuous and ill-considered actions and decisions.” Juveniles are also more susceptible than adults to “negative influences” and peer pressure. Finally, the character of juveniles is not as well formed, and their personality traits are “more transitory, less fixed.” 8 Footnote
543 U.S. at 569, 570 . For these reasons, irresponsible conduct by juveniles is “not as morally reprehensible,” they have “a greater claim than adults to be forgiven,” and “a greater possibility exists that a minor’s character deficiencies will be reformed.” 9 Footnote
543 U.S. at 570 . Because of the diminished culpability of juveniles, the penological objectives of retribution and deterrence do not provide adequate justification for imposition of the death penalty. The majority preferred a categorical rule over individualized assessment of each offender’s maturity, explaining that “[t]he differences between juvenile and adult offenders are too marked and well understood to risk allowing a youthful person to receive the death penalty despite insufficient culpability.” 10 Footnote
543 U.S. at 572–573 . Strongly disagreeing, Justice O’Connor wrote that “an especially depraved juvenile offender may . . . be just as culpable as many adult offenders considered bad enough to deserve the death penalty. . . . [E]specially for 17-year-olds . . . the relevant differences between ‘adults’ and ‘juveniles’ appear to be a matter of degree, rather than of kind.” Id. at 600 .

The Roper Court found confirmation for its holding in “the overwhelming weight of international opinion against the juvenile death penalty.” 11 Footnote
543 U.S. at 578 (noting “the stark reality that the United States is the only country in the world that continues to give official sanction to the juvenile death penalty,” id. at 575 ). Although “not controlling,” the rejection of the juvenile death penalty by other nations and by international authorities was “instructive,” as it had been in earlier cases, for Eighth Amendment interpretation.12 Footnote
543 U.S. at 577, 578 . Citing as precedent Trop v. Dulles, 356 U.S. 86, 102–03 (1958) (plurality opinion); Atkins , 536 U.S. at 317 n.21 ; Enmund v. Florida, 458 U.S. 782, 796–97, n.22 (1982) , Thompson v. Oklahoma, 487 U.S. 815, 830–31 & n.31 (1988) (plurality opinion); and Coker v. Georgia, 433 U.S. 584, 596 n.10 (1977) (plurality opinion).

Footnotes 1 Thompson v. Oklahoma, 487 U.S. 815 (1988) . 2 Wilkins v. Missouri was decided along with Stanford . 3 Compare Thompson , 487 U.S. at 849 (O’Connor, J., concurring) (two-thirds of all state legislatures had concluded that no one should be executed for a crime committed at age 15, and no state had “unequivocally endorsed” a lower age limit) with Stanford , 492 U.S. at 370 (15 of 37 states permitting capital punishment decline to impose it on 16-year-old offenders; 12 decline to impose it on 17-year-old offenders). 4 536 U.S. at 314, n.18 . 5 543 U.S. 551 (2005) . The case was decided by 5-4 vote. Justice Kennedy wrote the Court’s opinion, and was joined by Justices Stevens, Souter, Ginsburg, and Breyer. Justice O’Connor, who had joined the Court’s 6-3 majority in Atkins , wrote a dissenting opinion, as did Justice Scalia, who was joined by Chief Justice Rehnquist and Justice Thomas. 6 Dissenting in Roper , Justice O’Connor disputed the consistency of the trend, pointing out that since Stanford two states had passed laws reaffirming the permissibility of executing 16- and 17-year-old offenders. 543 U.S. at 596 . 7 543 U.S. at 564 . The Stanford Court had been split over the appropriate scope of inquiry in cruel and unusual punishment cases. Justice Scalia’s plurality would have focused almost exclusively on an assessment of what the state legislatures and Congress have done in setting an age limit for application of capital punishment. 492 U.S. at 377 ( “A revised national consensus so broad, so clear and so enduring as to justify a permanent prohibition upon all units of democratic government must appear in the operative acts (laws and the application of laws) that the people have approved.” ). The Stanford dissenters would have broadened this inquiry with a proportionality review that considers the defendant’s culpability as one aspect of the gravity of the offense, that considers age as one indicator of culpability, and that looks to other statutory age classifications to arrive at a conclusion about the level of maturity and responsibility that society expects of juveniles. 492 U.S. at 394–96 . The Atkins majority adopted the approach of the Stanford dissenters, conducting a proportionality review that brought their own “evaluation” into play along with their analysis of consensus on the issue of executing persons with intellectual disabilities. 8 543 U.S. at 569, 570 . 9 543 U.S. at 570 . 10 543 U.S. at 572–573 . Strongly disagreeing, Justice O’Connor wrote that “an especially depraved juvenile offender may . . . be just as culpable as many adult offenders considered bad enough to deserve the death penalty. . . . [E]specially for 17-year-olds . . . the relevant differences between ‘adults’ and ‘juveniles’ appear to be a matter of degree, rather than of kind.” Id. at 600 . 11 543 U.S. at 578 (noting “the stark reality that the United States is the only country in the world that continues to give official sanction to the juvenile death penalty,” id. at 575 ). 12 543 U.S. at 577, 578 . Citing as precedent Trop v. Dulles, 356 U.S. 86, 102–03 (1958) (plurality opinion); Atkins , 536 U.S. at 317 n.21 ; Enmund v. Florida, 458 U.S. 782, 796–97, n.22 (1982) , Thompson v. Oklahoma, 487 U.S. 815, 830–31 & n.31 (1988) (plurality opinion); and Coker v. Georgia, 433 U.S. 584, 596 n.10 (1977) (plurality opinion).