John Q. Hamm, Commissioner, Alabama Department of Corrections v. Joseph Clifton Smith
No. 24-872 · Decided May 21, 2026
Whether and how courts may consider the cumulative effect of multiple IQ scores when assessing a claim that a defendant is intellectually disabled under *Atkins v. Virginia*. The Court dismissed the writ of certiorari as improvidently granted, leaving the lower court's decision undisturbed.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
Parties — Petitioner: JOHN Q. HAMM, COMMISSIONER, ALABAMA DEPARTMENT OF CORRECTIONS · Respondent: JOSEPH CLIFTON SMITH
Vote & lineupPer Curiam
Who prevailed — The respondent prevailed because the Court dismissed the petition, leaving in place the lower court's ruling that he is intellectually disabled and cannot be executed.
The question

Whether and how courts may consider the cumulative effect of multiple IQ scores when assessing a claim that a defendant is intellectually disabled under *Atkins v. Virginia*. The Court also considered whether a State can require a claimant to prove an IQ of 70 or less by a preponderance of the evidence. Additionally, the Court examined whether courts must find that every valid score of "about" 75 or less supports such a claim.

Petitioner's argument
  • A factfinding court must consider the "cumulative effect" of multiple IQ scores, meaning the scores must be combined to prove an IQ of 70 or below.
  • Courts could use several methods to aggregate scores, such as taking the median, calculating a composite score, taking the average, or looking only at the highest score.
  • The District Court erred by failing to use a specific mathematical method to combine scores and instead relying on a "holistic" approach.
  • The respondent failed to prove an IQ of 70 or below by a preponderance of the evidence.
Respondent's argument
  • Courts must assess multiple IQ scores "holistically," which includes considering those scores in light of other evidence, particularly expert testimony regarding the scores' validity and meaning.
  • The analysis should include other evidence of the claimant's intellectual functioning, such as academic achievement and executive functioning.
  • The District Court's finding that the respondent is intellectually disabled was based on a proper consideration of IQ test results in the context of expert testimony and adaptive deficits.
  • The respondent's scores, when viewed holistically and considering the standard error of measurement, support a finding of intellectual disability.
The decision
  • The Court dismissed the writ of certiorari as improvidently granted.
  • The Court declined to provide a specific test or rule for evaluating multiple IQ scores.
  • The Court did not resolve the questions regarding the 70-IQ cutoff or the preponderance of the evidence standard.
  • The Court did not reverse or affirm the lower court's specific factual findings regarding the respondent's intellectual disability.
  • The Court noted that *Atkins v. Virginia* left it to the States to "develop appropriate ways to enforce" the limitation on executing intellectually disabled persons.
  • The Court reasoned that it was not equipped to provide meaningful guidance because the litigation below did not focus on whether a precise methodology exists that courts must use.
  • The Court observed that the parties agreed there is no single, mechanical rule for aggregating multiple IQ scores.
  • The Court concluded that it should not provide detailed guidance beyond what its previous cases have already stated.
Separate opinions
SOTOMAYOR, concurring, joined by JACKSON
  • Argues the Court cannot provide guidance because the evidentiary record and the way the case proceeded below were not trained on the specific theories now advanced by the parties.
  • Contends the District Court's "holistic" approach is consistent with *Hall v. Florida* and *Moore v. Texas*, which emphasize that IQ scores are imprecise and must be considered alongside other evidence.
  • Notes that the medical community, including the American Psychological Association and the American Association on Intellectual and Developmental Disabilities, supports the use of clinical judgment and the consideration of adaptive deficits when scores are near the boundary of intellectual disability.
THOMAS, dissenting, joined by nobody
  • Argues that *Atkins v. Virginia* should be overruled because it is not supported by the original meaning of the Eighth Amendment.
  • Claims the Eighth Amendment prohibits cruel and unusual *methods* of punishment, not the execution of people based on IQ scores.
  • Asserts the respondent is not intellectually disabled because he reads at an 11th-grade level and never received a score of 70 or below.
ALITO, dissenting, joined by THOMAS, and the Chief Justice and GORSUCH as to Parts I, III, and IV
  • Argues the Court should have provided guidance on how to apply a 70-IQ cutoff with multiple scores to avoid "battles of experts" and arbitrary outcomes.
  • Proposes three sound methods for estimating "true" IQ based on the *APA Handbook of Intellectual and Developmental Disabilities*: calculating a composite score, taking the median value, or using expert judgment on "central tendency."
  • Contends the lower courts' "one-low-score" and "holistic" approaches are statistically and psychologically unsound and contravene the ruling in *Moore v. Texas*.
Read the full opinion on supremecourt.gov (PDF) →