The U.S. Supreme Court has declined to step in to resolve festering disputes about the scope of the protections its prior rulings afford to intellectually disabled death-row prisoners. On July 2, 2020, the Court denied petitions to review three such cases, allowing death sentences in Alabama and Tennessee to stand despite the application of unconstitutionally restrictive standards in assessing a prisoner’s intellectual disability, while rebuffing Oklahoma’s efforts to undo a lower court ruling that had applied the Court’s decisions to declare an intellectually disabled prisoner ineligible for the death penalty.

The three cases address three applications of Atkins v. Virginia, the 2002 U.S. Supreme Court decision that found it is unconstitutional to execute people with intellectual disabilities. The petitions raised questions about how states have implemented Atkins and the applicability of subsequent cases, including Hall v. Florida, a 2014 case that struck down Florida’s strict IQ cutoff for finding impairments in intellectual functioning, and Moore v. Texas, which in 2017 struck down Texas’ unscientific standard for determining deficits in adaptive functioning.

In Sharp v. Smith, the Court’s decision will allow a federal appeals court’s grant of relief to an Oklahoma death-row prisoner stand. In the other two cases, Keen v. Tennessee and Smith v. Dunn, the Court’s denial of a hearing leaves in place decisions that favor the state.

The diagnostic criteria for determining intellectual disability are well established. To be considered intellectually disabled, a person must have significantly subaverage intellectual functioning, significant deficits in adaptive functioning, and an onset of the disability during the developmental period, typically defined as age 18. In both Hall and Moore, the Court rebuked the states for using outlier practices that ignored prevailing medical standards for diagnosing intellectual disability.

In Sharp, Oklahoma prosecutors sought Supreme Court review of a federal appeals court decision that found Roderick L. Smith ineligible for the death penalty because of his intellectual disability. A panel of the U.S. Court of Appeals for the Tenth Circuit applied the principles set forth in Moore to Smith’s case and concluded that “no rational trier of fact could have found that Smith did not meet the adaptive-functioning prong” of the criteria for determining intellectual disability. The state of Oklahoma argued that the court should not have applied Moore to Smith’s case because Moore had not been decided by the time the Oklahoma courts first considered Smith’s appeal.

In Keen v. Tennessee, death-row prisoner David Keen’s lawyers argued that the Tennessee courts had “closed the courthouse doors” to intellectually disabled prisoners by failing to establish a procedural mechanism under which they can present their claims. Keen identified 14 cases in which the Tennessee courts had ruled that no procedural mechanism existed to hear claims that prisoners were ineligible for execution because of intellectual disability. The Tennessee Supreme Court, Keen said, has recognized that without such a mechanism the state may unconstitutionally execute an intellectually disabled prisoner, but the court has failed to create any process for litigating these claims. In addition, while the court has urged the legislature to create a procedural mechanism for litigating intellectual disability in capital cases, the legislature has not done so. “Without clarification from this Court,” Keen’s petition argued, “Tennessee will not only execute an intellectually disabled man, but will, through inaction, limit the constitutional protection recognized by this Court in Atkins v. Virginia.” The Supreme Court’s decision not to hear Keen’s case allows Tennessee’s denial of relief to stand.

The third case, Smith v. Dunn, was an appeal from Alabama death-row prisoner Willie B. Smith III. Alabama had denied Smith’s claim of intellectual disability, saying he had not proven sufficiently impaired intellectual or adaptive functioning. However, it rejected the intellectual functioning portion of his claim on the grounds that his IQ score, unadjusted for measurement errors, was 72 — two IQ points above the state’s unconstitutional IQ cutoff requirement of 70. It rejected his claim of adaptive deficits by unconstitutionally focusing on his adaptive skills and asserting that those skills outweighed his deficits. Hall explicitly declared the use of IQ cut-off scores to be unconstitutional and Moore explicitly stated that the focus of the determination of adaptive functioning is on the presence or absence of deficits, not on whether there are countervailing strengths.

The U.S. Court of Appeals for the Eleventh Circuit agreed that Smith would be ineligible for execution had Alabama applied a constitutionally valid standard for determining intellectual disability, but denied relief on the grounds that Hall and Moore should be applied only to cases that had not yet been decided on appeal at the time of the Supreme Court decisions. Whether Smith could be executed, the court ruled, was purely “a matter of timing”: if he was tried after Hall and Moore had been decided, he would not have been eligible for the death penalty.

Smith further argued that the federal circuit courts were split as to whether Hall and Moore should apply to all intellectual disability cases or should have only prospective application. The Supreme Court’s denial of review left that circuit split unresolved and allowed Smith’s death sentence to stand.


Nolan Clay and Chris Casteel, Supreme Court lets stand deci­sion over­turn­ing death sen­tences, The Oklahoman, July 3, 2020; Jordan S. Rubin, U.S. Supreme Court Rejects Intellectual Disability Capital Cases, Bloomberg Law, July 22020.

Read fil­ings in Sharp v. Smith, Keen v. Tennessee, and Smith v. Dunn.