In case you've not read the ruling, here is what I find troublesome ~
From Justice Kennedy's delivery of the opinion of the court: (Justices Stevens, Souter, Ginsburg and Breyer supported).
"... The objective indicia of national consensus here -
the rejection of the juvenile death penalty in the majority of states;
the infrequency of its use even where it remains on the books;
and the consistency in the trend toward abolition of the practice -
provide sufficient evidence that today society views juveniles ... as "categorically less culpable than the average criminal." ...
Capital punishment must be limited to those offenders who commit "a narrow category of the most serious crimes" and whose extreme culpability makes them "the most deserving of execution."
Three general differences between juveniles under 18 and adults demonstrate that juvenile offenders cannot with reliability be classified among the worst offenders.
Juveniles' susceptibility to immature and irresponsible behavior means their irresponsible conduct is not as morally reprehensible as that of an adult. ...
Their own vulnerability and comparative lack of control over their immediate surroundings mean juveniles have a greater claim than adults to be forgiven for failing to escape negative influences in their whole environment. ...
The reality that juveniles still struggle to define their identity means it is less supportable to conclude that even a heinous crime committed by a juvenile is evidence of irretrievably depraved character.
The overwhelming weight of international opinion against the juvenile death penalty is not controlling here, but provides respected and significant confirmation for the court's determination that the penalty is disproportionate punishment for offenders under 18.
In a dissenting opinion, Justice Antonin Scalia chastised his colleagues for taking power from the states. "The court thus proclaims itself sole arbiter of our nation's moral standards," Scalia wrote. The graph below indicates current state stats:
Justice Scalia filed a dissenting opinion (in which Chief Justice Rehnquist and Justice Thomas joined) which stated:
"As we have noted in prior cases, the evidence is unusually clear that the Eighth Amendment was not originally understood to prohibit capital punishment for 16- and 17-year-old offenders.
But the court having pronounced that the Eighth Amendment is an ever-changing reflection of "the evolving standards of decency" of our society, it makes no sense for the justices then to prescribe those standards rather than discern them from the practices of our people. On the evolving-standards hypothesis, the only legitimate function of this court is to identify a moral consensus of the American people. By what conceivable warrant can nine lawyers presume to be the authoritative conscience of the nation? "
I totally agree with Justice Scalia ~ this unlawful decision presents a threat to us all.
I agree, too, with Justice Sandra Day O'Connor who wrote a dissenting opinion that included:
" Adolescents as a class are undoubtedly less mature, and therefore less culpable for their misconduct, than adults. But the court has adduced no evidence impeaching the seemingly reasonable conclusion reached by many state legislatures: that at least some 17-year-old murderers are sufficiently mature to deserve the death penalty in an appropriate case.
An especially depraved juvenile offender may nevertheless be just as culpable as many adult offenders considered bad enough to deserve the death penalty. Similarly, the fact that the availability of the death penalty may be less likely to deter a juvenile from committing a capital crime does not imply that this threat cannot effectively deter some 17-year-olds from such an act.
... Some juvenile murderers may be quite mature. Chronological age is not an unfailing measure of psychological development, and common experience suggests that many 17-year-olds are more mature than the average young "adult." "