The prohibition on mandatory life without parole sentences for juveniles convicted of homicide offenses announced in Miller v. Alabama (2012) is a substantive rule that applies retroactively in state collateral review proceedings, the U.S. Supreme Court held Jan. 25.

The case is Montgomery v. Louisiana.

Miller had held that the 8th Amendment prohibits sentencing a juvenile convicted of homicide to life in prison without parole absent consideration of the juvenile’s diminished culpability because of youth and capacity for change.    


In the 1960s, Henry Montgomery was convicted of a murder committed when he was 17 years old.  He was sentenced to life without parole, and has been held ever since.

After Miller was decided, he sought state collateral review of his sentence, claiming that it was an unlawful sentence.

The Louisiana Supreme Court held that Miller was not retroactive and denied relief.

Jurisdictional Question

In a 6-3 decision, the U.S. Supreme Court addressed two questions:  First, whether the Court had jurisdiction over the state collateral review proceeding, and second, whether Miller was a substantive rule that is retroactive.

The jurisdictional question was premised on the notion that state collateral review only determines the scope of relief available in a particular type of state proceeding, which is a question of state law beyond the U.S. Supreme Court’s power to review. 

However, the Supreme Court rejected this view, and held that “where the Constitution establishes a rule and requires that the rule have retroactive application, then a state court’s refusal to give the rule retroactive effect is reviewable by this Court.”

“States may not disregard a controlling, constitutional command in their own courts,” the Court said. 

Under the Supremacy Clause, “[w]here state collateral review proceedings permit prisoners to challenge the lawfulness of their confinement, States cannot refuse to give retroactive effect to a substantive constitutional right that determines the outcome of that challenge,” the Court said.

The Court expressly limited this holding to “substantive rules,” and did not address whether this also applies to watershed rules of procedure.

The Court had held in Teague v. Lane (1989) that new constitutional rules do not apply retroactively to convictions that were final, except when the new rule is a “substantive rule of constitutional law,” or is a “watershed rule of criminal procedure implicating the fundamental fairness and accuracy of the criminal proceedings.”

Miller Announced Substantive Rule

“Substantive rules include ‘rules forbidding criminal punishment of certain primary conduct,’ as well as ‘rules prohibiting a certain category of punishment for a class of defendants because of their status or offense,” the Court said.

“Because Miller determined that sentencing a child to life without parole is excessive for all but ‘the rare juvenile offender whose crime reflects irreparable corruption,’ … it rendered life without parole an unconstitutional penalty for ‘a class of defendants because of their status,” the Court ruled. 

The Court ruled, however, that States need not “relitigate sentences” imposed in violation of Miller.  “A State may remedy a Miller violation by permitting juvenile homicide offenders to be considered for parole, rather than by resentencing them,” the Court said.