Roper v. Simmons is the 2005 U.S. Supreme Court decision that ruled it unconstitutional to execute anyone for a crime committed before the age of eighteen. By a 5–4 vote, the Court held that the death penalty for juvenile offenders violates the Eighth Amendment’s ban on cruel and unusual punishment, and it overturned a 1989 precedent that had allowed such executions.1Justia. Roper v. Simmons Seventy-one death sentences in twelve states were vacated the day the decision came down.
The Defendant and the Crime
Christopher Simmons was seventeen in September 1993 when he told two younger friends he wanted to burglarize a home and kill someone, reassuring them they could get away with it because they were minors.2Justia. State v. Simmons Simmons and fifteen-year-old Charlie Benjamin broke into Shirley Crook’s home, bound her, drove her to a state park, and threw her from a railroad trestle into the Meramec River, where she drowned.3Cornell Law Institute. Roper v. Simmons Simmons bragged about the killing afterward and was quickly arrested. A jury convicted him of first-degree murder and recommended death; the trial court imposed the sentence.
How the Case Reached the Supreme Court
Simmons’ death sentence survived his direct appeals and sat in place for years. Then in 2002, the Supreme Court decided Atkins v. Virginia, holding that executing people with intellectual disabilities violates the Eighth Amendment because their diminished moral responsibility makes the punishment disproportionate.4Justia. Atkins v. Virginia – 536 U.S. 304 (2002)
The Missouri Supreme Court read Atkins as pointing toward the same conclusion for juveniles, whose brains and characters are still forming. It stayed Simmons’ execution, threw out his death sentence, and resentenced him to life without parole. Missouri appealed, and the U.S. Supreme Court took the case to decide whether the juvenile death penalty could stand anywhere in the country.
The Holding
On March 1, 2005, the Court answered no. Justice Anthony Kennedy wrote the majority opinion, joined by Justices Stevens, Souter, Ginsburg, and Breyer.1Justia. Roper v. Simmons The rule is categorical: no person may be executed in the United States for a crime committed before their eighteenth birthday, whatever the facts of the offense.
The decision expressly overruled Stanford v. Kentucky, the 1989 case that had allowed the execution of sixteen- and seventeen-year-olds.5Justia. Stanford v. Kentucky Every juvenile death sentence in the country was invalidated at once.
The Majority’s Reasoning
A National Consensus Against the Practice
Eighth Amendment cases turn on whether a punishment offends contemporary standards of decency, and the Court measures those standards largely by counting states. By 2005, thirty states prohibited the juvenile death penalty: twelve had rejected capital punishment altogether, and eighteen more kept it but excluded juveniles.1Justia. Roper v. Simmons In the sixteen years since Stanford, five states had abandoned juvenile executions and none had moved the other direction. Even where the practice remained legal, it was rare. Kennedy called that pattern a national consensus.
Why Juveniles Are Different
The majority then explained why juveniles are categorically less culpable than adults, resting on three differences.6Library of Congress. Roper v. Simmons, 543 U.S. 551 (2005) Young people lack the maturity and sense of responsibility of adults, which produces impulsive and poorly considered choices. They are more vulnerable to negative influences and peer pressure, with less power to escape harmful environments. And their characters are still forming, so a bad act at seventeen is less reliable evidence of a fixed identity than the same act by an adult.
From those differences, Kennedy concluded that the two justifications for capital punishment do not fit juveniles. Retribution requires proportional blame, and juveniles carry less. Deterrence assumes rational weighing of consequences, which adolescent development makes less likely.
Scientific and International Support
The Court drew on amicus briefs from groups including the American Psychological Association, which presented research on adolescent impulsivity, risk-taking, peer orientation, and a short time horizon that leads teenagers to discount long-term consequences. The APA also pointed to brain imaging showing continued development into young adulthood in regions tied to decision-making, and argued that no reliable prediction can be made about whether a given juvenile will remain dangerous as an adult.
Kennedy also cited international practice. The United Nations Convention on the Rights of the Child and the International Covenant on Civil and Political Rights both bar the juvenile death penalty, and Kennedy noted that world opinion overwhelmingly opposed it. He treated that not as binding law but as confirmation that the practice was out of step with widely shared norms.
The Dissents
Justice Scalia, joined by Chief Justice Rehnquist and Justice Thomas, accused the majority of legislating. He rejected the national consensus finding, noting that twenty states still allowed the juvenile death penalty, and he argued the question belonged to state legislatures. He objected sharply to the use of international law to interpret the American Constitution.1Justia. Roper v. Simmons
Justice O’Connor dissented separately on narrower grounds. She too thought the majority overstated the consensus, but her main objection was the categorical rule. She would have kept individualized sentencing, allowing execution of an unusually mature and calculating seventeen-year-old whose youth did not meaningfully reduce culpability. The blanket ban, in her view, ignored real differences among juvenile defendants.
What Roper Changed for Juvenile Sentencing
Roper set a constitutional principle that reached beyond the death penalty: young offenders are different, and sentencing must recognize it. The Court has returned to that idea several times.
Graham v. Florida (2010) held that life without parole for a juvenile who did not commit homicide violates the Eighth Amendment, and required states to give those offenders a meaningful chance at release.7Cornell Law Institute. Graham v. Florida
Miller v. Alabama (2012) struck down mandatory life without parole for juvenile homicide offenders. The sentence is still available, but a sentencing court must weigh the defendant’s youth and its consequences before imposing it.8Justia. Miller v. Alabama, 567 U.S. 460 (2012)
Montgomery v. Louisiana (2016) made Miller retroactive, allowing prisoners serving mandatory life-without-parole sentences for juvenile crimes to seek resentencing or parole eligibility.9Justia. Montgomery v. Louisiana, 577 U.S. 190 (2016) The Court stressed that even children who commit terrible crimes are capable of change.
Jones v. Mississippi (2021) pulled back on how far Miller and Montgomery went. A sentencing judge does not need to make a separate factual finding that a juvenile is permanently incorrigible before imposing life without parole; discretion to consider youth is enough. The Roper rule itself was not disturbed.
More than half of U.S. states have now gone beyond what the Supreme Court requires and legislatively ended or effectively abolished juvenile life without parole. The direction Roper identified in 2005 has continued.