Дело Аткинс против Вирджинии: Ограничения смертной казни для лиц с интеллектуальными нарушениями.

Atkins v. Virginia, 536 U. S. 304 (2002), is a case in which the Supreme Court of the United States ruled 6–3 that executing people with intellectual disabilities violates the Eighth Amendment's ban on cruel and unusual punishments, but that states can define who has an intellectual disability. At the time Atkins was decided, just 18 of the 38 death penalty states exempted mentally disabled offenders from the death penalty. Twelve years later in Hall v. Florida the U. S. Supreme Court narrowed the discretion under which U. S. states can designate an individual convicted of murder as too intellectually incapacitated to be executed.

Twelve years after its Atkins decision the U. S. Supreme Court narrowed in Hall v. Florida (2014) the discretion under which U. S. states can designate an individual convicted of murder as too intellectually incapacitated to be executed. The Court laid down as a legal rule that "if the individual claiming intellectual incapacity has an IQ score that falls somewhere between 70 and 75, then that individual's lawyers must be allowed to offer additional clinical evidence of intellectual deficit, including, most importantly, the inability to learn basic skills and [to] adapt how to react to changing circumstances." "A diagnosis of intellectual disability requires three things: 1) significantly subaverage intellectual functioning (typically measured by an IQ score roughly two standard deviations below the mean); 2) adaptive functioning deficits; and 3) an onset during childhood, before reaching 18. As the court recognized in Hall v. Florida (2014), intellectual disability is a condition, not an IQ score, and proper diagnosis thus places great emphasis on the second requirement, related to adaptive functioning." and that courts should base their decisions on opinions of professional organizations like the American Psychological Association.

A jury in Virginia decided in July 2005 that Atkins was intelligent enough to be executed on the basis that the constant contact he had with his lawyers provided intellectual stimulation and raised his IQ above 70, making him competent to be put to death under Virginia law. The prosecution had argued that his poor school performance was caused by his use of alcohol and drugs and that his lower scores in earlier IQ tests were tainted. In January 2008, Circuit Court Judge Prentis Smiley, who was revisiting the matter of whether Atkins was mentally disabled, received allegations of prosecutorial misconduct. Those allegations, if true, would have authorized a new trial for Atkins. After two days of testimony on the matter, Smiley determined that prosecutorial misconduct had occurred. At that juncture, Smiley could have vacated Atkins's conviction and ordered a new trial. Instead, Smiley determined the evidence was overwhelming that Atkins had participated in a felony murder and commuted Atkins's sentence to life in prison. Prosecutors sought writs of mandamus and prohibition in the Virginia Supreme Court on the matter, claiming that Smiley had exceeded his judicial authority with his ruling. On June 4, 2009, the Virginia Supreme Court, in a 5 2 decision authored by Chief Justice Leroy R. Hassell Sr., ruled that neither mandamus nor prohibition was available to overturn the court's decision to commute the sentence. Justice Cynthia D. Kinser, joined by Justice Donald W. Lemons, considered the two most conservative justices of the Court, wrote a lengthy dissent that was highly critical of both the majority's reasoning and the action of the circuit court in commuting the sentence.