Roper v. Simmons, decided on March 1, 2005, is the U.S. Supreme Court decision that made it unconstitutional to execute anyone for a crime committed before age eighteen. By a 5–4 vote, the Court held that the Eighth Amendment’s ban on cruel and unusual punishment, applied to the states through the Fourteenth Amendment, forbids the juvenile death penalty. The ruling overturned a 1989 precedent, wiped out juvenile death sentences on death rows across the country, and became the foundation for a series of later cases limiting how harshly juveniles can be sentenced.1Justia U.S. Supreme Court Center. Roper v. Simmons
What the Court Held
The majority drew a categorical line at age eighteen. No state may impose the death penalty on someone who was younger than eighteen at the time of the offense, regardless of the crime. Justice Anthony Kennedy wrote the opinion, joined by Justices Stevens, Souter, Ginsburg, and Breyer. Chief Justice Rehnquist and Justices Scalia, O’Connor, and Thomas dissented. The decision expressly overruled Stanford v. Kentucky (1989), which had allowed capital punishment for sixteen- and seventeen-year-old offenders, and it affirmed the Missouri Supreme Court’s decision to resentence Christopher Simmons to life imprisonment without eligibility for probation, parole, or release except by act of the governor.1Justia U.S. Supreme Court Center. Roper v. Simmons
How the Case Reached the Supreme Court
In 1993, seventeen-year-old Christopher Simmons planned and carried out the murder of Shirley Crook in Missouri, telling friends beforehand that they could “get away with it” because they were minors. A jury convicted him of first-degree murder, and the trial court sentenced him to death.1Justia U.S. Supreme Court Center. Roper v. Simmons
His case reopened after the Supreme Court decided Atkins v. Virginia in 2002, which barred executions of people with intellectual disabilities on Eighth Amendment grounds.2Justia U.S. Supreme Court Center. Atkins v. Virginia Applying the same reasoning to juveniles, the Missouri Supreme Court ruled 6–3 that a national consensus had formed against executing offenders who committed their crimes as minors. It set aside Simmons’s death sentence and resentenced him to life without release. Missouri appealed, and the U.S. Supreme Court took the case to decide whether the Eighth Amendment now barred what Stanford had permitted in 1989.1Justia U.S. Supreme Court Center. Roper v. Simmons
Why the Majority Ruled the Way It Did
A National Consensus Against Juvenile Executions
The majority worked from the doctrine that the Eighth Amendment draws its meaning from “evolving standards of decency that mark the progress of a maturing society.” By 2005, thirty states prohibited the juvenile death penalty: twelve had abolished capital punishment entirely, and eighteen retained it but excluded juveniles. Since Stanford, five states had moved to ban juvenile executions, and none had gone the other way. Even in states where the practice remained legal, actual executions of juvenile offenders had become rare. Kennedy read the direction and pace of change as evidence of a settled national judgment.1Justia U.S. Supreme Court Center. Roper v. Simmons
Juveniles Are Categorically Less Culpable
The Court then made its own judgment about whether the punishment fits the class of offender. It identified three differences between juveniles and adults. Teenagers lack the maturity and sense of responsibility that come with adulthood, which makes them more impulsive and reckless. They are more susceptible to negative peer pressure and have less control over their surroundings. And their character is still forming, so even a terrible crime is a weaker signal of a permanently depraved personality than the same crime committed by an adult.
An American Psychological Association amicus brief backed those observations with behavioral research on adolescent decision-making, impulsivity, risk-taking, peer orientation, and shortened time horizons, along with MRI evidence that regions of the brain involved in decision-making continue developing into young adulthood. The APA also argued that predicting future dangerousness in a teenager is not reliable enough to justify an irreversible sentence.3American Psychological Association. Roper v. Simmons
From those premises the Court concluded that neither major rationale for capital punishment fully applies to juveniles. Retribution requires punishment proportional to blameworthiness, and juveniles are less blameworthy. Deterrence assumes the offender weighs consequences, which is exactly what adolescents do less reliably than adults.
International Practice as Confirmation
Kennedy also noted that the United States stood essentially alone in permitting the juvenile death penalty. The U.N. Convention on the Rights of the Child, ratified by every country except the United States and Somalia at the time, forbids capital punishment for offenses committed by anyone under eighteen. The International Covenant on Civil and Political Rights contains the same prohibition, and the United States had ratified it only with a reservation preserving the juvenile death penalty. The majority treated global practice as confirmation of its reading of American standards rather than as an independent source of constitutional law.1Justia U.S. Supreme Court Center. Roper v. Simmons
The Dissents
Justice Scalia, joined by Chief Justice Rehnquist and Justice Thomas, wrote a sharp dissent accusing the majority of installing itself as “sole arbiter of our Nation’s moral standards.” He argued that “cruel and unusual” should be read as the ratifiers understood it, not remade every generation by five justices. He also attacked the consensus count as inflated, saying the majority padded its numbers by including states that had abolished capital punishment for everyone rather than making any specific judgment about juveniles. And he rejected any reliance on foreign law, writing that “acknowledgment of foreign approval has no place in the legal opinion of this Court.”4Cornell Law School. Supreme Court of the United States – Roper v. Simmons
Justice O’Connor dissented separately on narrower grounds. She agreed that the pattern of state legislation resembled the evidence the Court had relied on in Atkins, but she found a meaningful difference: at least eight states had recently considered and adopted laws permitting the execution of sixteen- and seventeen-year-olds, so the consensus was not as one-directional as in Atkins. She would have left the question to sentencing courts, arguing that differences in maturity between juveniles and adults are “neither universal nor significant enough to justify a rule excluding juveniles from the death penalty.” Unlike Scalia, she accepted that foreign legal standards can have some relevance to Eighth Amendment analysis.5Cornell Law School. Supreme Court of the United States – Roper v. Simmons
What Changed the Day of the Ruling
On the day Roper was decided, 71 people sat on death rows nationwide for crimes committed before they turned eighteen. Every one of those death sentences was vacated, and most of those prisoners were resentenced to life imprisonment. The ruling also invalidated juvenile death penalty statutes in the twenty states that still had them, whether or not those states had used them recently. For Simmons himself, the outcome was the life sentence the Missouri Supreme Court had already imposed.1Justia U.S. Supreme Court Center. Roper v. Simmons
What Roper Set in Motion
Roper‘s core idea, that children are “constitutionally different from adults for sentencing purposes,” became the seed of a broader line of Eighth Amendment cases reaching beyond capital punishment.
In Graham v. Florida (2010), the Court held that a juvenile convicted of a non-homicide offense cannot be sentenced to life without parole. States do not have to guarantee release, but they must give the offender “some meaningful opportunity to obtain release based on demonstrated maturity and rehabilitation.”6Justia U.S. Supreme Court Center. Graham v. Florida
Two years later, Miller v. Alabama (2012) struck down mandatory life-without-parole sentences for juvenile homicide offenders. Miller did not ban that sentence outright; it barred sentencing schemes that imposed it automatically, without letting the judge weigh the offender’s youth and individual circumstances.7Justia U.S. Supreme Court Center. Miller v. Alabama
Montgomery v. Louisiana (2016) then made Miller retroactive, treating it as a substantive rule that prohibits a category of punishment for a class of people. States could comply by holding new sentencing hearings or by extending parole eligibility to those already serving mandatory juvenile life-without-parole sentences.8Justia U.S. Supreme Court Center. Montgomery v. Louisiana
Most recently, Jones v. Mississippi (2021) pulled back. It held that a judge sentencing a juvenile to life without parole does not have to make a separate finding of “permanent incorrigibility”; a discretionary sentencing scheme in which the judge has authority to consider youth is enough, even without an on-the-record explanation of why that youth did not change the result. Critics argue the ruling weakens Miller‘s promise of individualized sentencing.9Justia U.S. Supreme Court Center. Jones v. Mississippi
Together, these decisions leave Roper‘s categorical rule intact at the top, an absolute bar on executing juvenile offenders, while leaving states considerable room to decide how much youth should matter in the sentences below it.