Case Miller v Alabama

(a) The Eighth Amendment’s prohibition of cruel and unusual punishment “guarantees individuals the right not to be subjected to excessive sanctions.” Roper v. Simmons, 543 U. S. 551, 560. That right “flows from the basic ‘precept of justice that punishment for crime should be graduated and proportioned’ ” to both the offender and the offense.

Two strands of precedent reflecting the concern with proportionate punishment come together here. The first has adopted categorical bans on sentencing practices based on mismatches between the culpability of a class of offenders and the severity of a penalty. See, e.g., Kennedy v. Louisiana, 554 U. S. 407. Several cases in this group have specially focused on juvenile offenders, because of their lesser culpability. Thus, Roper v. Simmons held that the Eighth Amendment bars capital punishment for children, and Graham v. Florida, 560 U. S. ___, concluded that the Amendment prohibits a sentence of life without the possibility of parole for a juvenile convicted of a nonhomicide offense. Graham further likened life without parole for juveniles to the death penalty, thereby evoking a second line of cases. In those decisions, this Court has required sentencing authorities to consider the characteristics of a defendant and the details of his offense before sentencing him to death. See, e.g., Woodson v. North Carolina, 428 U. S. 280 (plurality opinion). Here, the confluence of these two lines of precedent leads to the conclusion that mandatory life without parole for juveniles violates the Eighth Amendment.

Graham, Roper, and our individualized sentencing decisions make clear that a judge or jury must have the opportunity to consider mitigating circumstances before imposing the harshest possible penalty for juveniles. By requiring that all children convicted of homicide receive lifetime incarceration without possibility of parole, regardless of their age and age-related characteristics and the nature of their crimes, the mandatory sentencing schemes before us violate this principle of proportionality, and so the Eighth Amendment’s ban on cruel and unusual punishment.