Why People with Intellectual Disability Are Exempt from the Death Penalty

In 2002, the Supreme Court held in Atkins v. Virginia that it would be cruel and unusual punishment to sentence people with intellectual disability to death. (The Court used the correct terminology at the time, referring to individuals with “mental retardation.”) At the time, 18 states exempted this group from capital punishment, and the Court determined that the “legislative judgment reflects a much broader social and professional consensus” that executing individuals with intellectual disability was an excessive punishment not in accord with our standards of decency. Justice Stevens, delivering the opinion of the Court, wrote:

Mentally retarded persons frequently know the difference between right and wrong and are competent to stand trial, but, by definition, they have diminished capacities to understand and process information, to communicate, to abstract from mistakes and learn from experience, to engage in logical reasoning, to control impulses, and to understand others’ reactions. Their deficiencies do not warrant an exemption from criminal sanctions, but diminish their personal culpability.

The Court doubted that the justifications underpinning the death penalty – retribution and deterrence – applied to intellectually disabled offenders. Justice Stevens wrote:

As to retribution, the severity of the appropriate punishment necessarily depends on the offender’s culpability. If the culpability of the average murderer [that is, a murderer whose crime involves no special aggravating circumstances] is insufficient to justify imposition of death, the lesser culpability of the mentally retarded offender surely does not merit that form of retribution. As to deterrence, the same cognitive and behavioral impairments that make mentally retarded defendants less morally culpable also make it less likely that they can process the information of the possibility of execution as a penalty and, as a result, control their conduct based upon that information.

The Court cited the higher probability of inaccurate factual determinations of guilt and individual culpability due to the increased potential that defendants with intellectual disability would “unwittingly confess to crimes they did not commit.” For example, Earl Washington, who had an IQ of 69, faced execution after confessing to a crime he did not commit. In 1983, police convinced Washington to make a statement concerning the 1982 rape and murder of a woman in Culpepper, VA. The statements were used against him, and in 1984 he was convicted and sentenced to death. Sixteen years later, DNA tests confirmed that Washington was innocent and he received an absolute pardon.

The Atkins opinion also suggested that “[m]entally retarded defendants may be less able to give meaningful assistance to their counsel and are typically poor witnesses, and their demeanor may create an unwarranted impression of lack of remorse for their crimes.”