Hamm v. Smith

Brief filed: 9/25
Court: Supreme Court of the United States 
Year of Decision: 2026

Read full-text amicus brief (PDF, 223KB)opens in new window

Whether and how courts may consider the cumulative effect of multiple IQ scores in assessing an Atkins claim.

Tests (Use, Validity, and Security of Psychological Tests and Test Data)

The case involves Joseph Clifton Smith, who has obtained five full-scale IQ scores ranging from 72 to 78. The proper interpretation of these scores is central to determining whether he meets the intellectual disability criteria that would exempt him from the death penalty under Atkins v. Virginia (2002). This case follows a previous SCOTUS decision (November 2024) where the Court vacated and remanded the case to the 11th Circuit for clarification on how multiple IQ scores should be evaluated in intellectual disability determinations.

The APA, joined by the American Psychiatric Association and Alabama Psychological Association, argues that diagnosing intellectual disability requires a comprehensive clinical assessment that goes beyond just IQ test scores. The brief emphasizes that IQ tests provide important but not definitive data, and that multiple IQ scores must be analyzed using established scientific methods and clinical judgment. Key points include: (1) experts should consider multiple IQ test scores in assessing Atkins claims because they provide additional data and nuance; (2) scientifically accepted methods must be used to aggregate scores—averaging scores or selecting the highest/lowest score are invalid approaches; 7(3) even when multiple scores are aggregated, the standard error of measurement cannot be eliminated entirely; and (4) diagnostic criteria are developed through rigorous scientific study and clinical experience and are applied in various settings beyond death penalty cases.

On May 21, 2026, the Supreme Court dismissed the writ of certiorari as improvidently granted. Justice Sotomayor, joined by Justice Jackson, concurred, explaining that the case was not an appropriate vehicle for the Court to give detailed guidance on how courts must evaluate multiple IQ scores under Atkins and that the lower courts’ holistic review was consistent with Supreme Court precedent, the medical community’s diagnostic framework, and Alabama law. Justice Thomas dissented, and Justice Alito also dissented, joined in whole or in part by Justice Thomas, the Chief Justice, and Justice Gorsuch, arguing that the Court should have provided guidance on analyzing multiple IQ scores in Atkins cases.