Atkins v. Virginia held that the death penalty is unconstitutional for people with intellectual disabilities.
The case concerned Daryl Renard Atkins, who was convicted of capital murder in Virginia and sentenced to death. Evidence presented at sentencing included a psychologist’s assessment placing his IQ at 59, although later testimony disputed aspects of his intellectual functioning. The Supreme Court reviewed whether executing a person with intellectual disability violated the Eighth Amendment.
In a 6–3 decision in 2002, the Court ruled that such executions violate the Eighth Amendment’s ban on cruel and unusual punishment. Justice John Paul Stevens’s majority opinion emphasized reduced culpability, diminished ability to understand consequences, and the heightened risk that juries may misinterpret limitations in communication or reasoning.
The Court relied partly on an emerging national consensus: 18 of the 38 death-penalty states had barred execution of people with intellectual disabilities by the time of the ruling. Atkins left states to develop procedures for determining eligibility, but later cases narrowed that discretion. Hall v. Florida, decided in 2014, rejected Florida’s rigid IQ cutoff, and Moore v. Texas, decided in 2017, required more careful reliance on accepted clinical standards.