Supreme Court Probes ‘Confusion’ Over Death Penalty IQ Tests

Conservative justices asked whether the Supreme Court needs to sharpen its guidance on how courts assess intellectual disability in death penalty cases, signaling concern that its precedents are misapplied.

The justices on Wednesday heard argument in the case of Joseph Smith, who was sentenced to death in Alabama for a 1997 robbery-murder despite evidence that he may have an intellectual disability.

After years of state and federal litigation, the US Court of Appeals for the Eleventh Circuit vacated his sentence. It found Smith met the standard set in Atkins v. Virginia based partly on a 1998 IQ score of 72.

Atkins bars the execution of individuals with “subaverage intellectual functioning,” but leaves states to define how to assess disability. The court later held that states must use current medical standards and look beyond a rigid IQ cutoff, including adaptive deficits.

Alabama told the justices the lower courts misapplied those rulings. The state said multiple IQ tests administered to Smith from 72 to 78 should’ve been weighed differently, and that the Eleventh Circuit gave undue consideration to the lowest score. Under Alabama law, a defendant must show both an IQ of 70 or below and childhood adaptive deficits.

Robert M. Overing of the Alabama Solicitor General’s Office urged the justices to set “meaningful ground rules” for how courts evaluate multiple test results. He suggested the highest score should carry added weight because defendants may have incentives to test lower.

The liberal justices appeared skeptical. Justice Ketanji Brown Jackson questioned whether Alabama had waived its argument by not raising it earlier. Justice Sonia Sotomayor accused Overing of making “something wholesale up” in claiming lower courts had split on how to apply Atkins and its progeny.

But several conservatives signaled more openness. Justice Samuel Alito said state courts were “struggling” to read the court’s instructions in Hall v. Florida and Moore v. Texas. Justice Neil Gorsuch suggested the case might not meet the threshold for federal habeas review.

“I agree there’s some confusion,” he said. “That’s why we took the case.”

Smith’s attorney, former US Solicitor General Seth Waxman of WilmerHale, said states are nearly unanimous that IQ scores alone can’t resolve intellectual disability.

“Every state, with the exception of Oklahoma, says IQ is not a substitute for actual intellectual function,” he said.

The Trump administration backed Alabama. Harry Graver, assistant to the solicitor general, said the Eleventh Circuit effectively substituted a possibility standard for the required preponderance burden.

A ruling that eases states’ path to finding defendants eligible for execution could disproportionately affect people of color. More than 80% of death sentences vacated for intellectual disability since 2002 have involved inmates of color, according to the Death Penalty Information Center.

The case is John Q. Hamm v. Joseph Clifton Smith, U.S., No. 24-872, argued on 12/10/25.