The U.S. Supreme Court heard oral arguments Wednesday morning in a case from Alabama to clarify the role of IQ scores in ruling who’s eligible for execution.
The case, Hamm v. Smith, involves a challenge to the state’s plan to execute Joseph Clifton Smith, an Alabama man who confessed to the murder of Durk Van Dam, who he beat to death during a 1997 Mobile County robbery.
Smith’s legal team has challenged the execution, arguing that Smith is intellectually disabled, barring him from being killed by the state.
The U.S. District Court for the Middle District of Alabama and the U.S. Court of Appeals for the Eleventh Circuit stayed Smith’s execution; however, the state appealed the decisions on the grounds that Smith could not “prove an IQ of 70 or less.”
An IQ below 70 is a key criterion for determining if someone is intellectually disabled.
The Supreme Court outlawed the execution of intellectually disabled individuals convicted of capital crimes in its 2002 ruling in Atkins v. Virginia.
However, the court left it up to states to determine their own definitions of intellectual disability.
The court later decided in Hall v. Florida that states cannot establish a rigid IQ test score baseline as the sole determining factor for deciding whether or not an individual has a disability, and that IQ scores should be more accurately viewed as a range, with the possibility of an individual’s IQ being within five points higher or lower than their score.
In order to prove an offender is intellectually disabled in Alabama, they must be shown to have substantially subaverage intellectual functioning measured by standardized testing instruments, such as IQ tests, a substantially subaverage adaptive functioning and the onset of disability before the age of 18.
Since his conviction, Smith has taken five full-scale IQ tests, achieving scores of 75, 74, 72, 78 and 74.
Alabama Principal Deputy Solicitor General Robert Overing argued Wednesday on behalf of the state that Smith’s highest score is the best available evidence of Smith’s cognitive function, as opposed to the possibility that his lowest scores classify him as intellectually disabled.
“Nothing in the Eighth Amendment bars the sentence Joseph Smith received for murdering Durk Van Dam nearly 30 years ago,” Overing argued. “Atkins created an exception for offenders known to be intellectually disabled, but Smith is not.”
“We have an argument that the highest score should be given more probative weight because there are many ways that an IQ test can underestimate IQ, if the offender is distracted, fatigued, ill, or because of the incentive to avoid the death penalty,” he said.
Smith’s legal representation, Seth Waxman, argued against the sole consideration of Smith’s highest available IQ score and against IQ’s use as the sole metric for determining substantially subaverage intellectual functioning.
Waxman highlighted that Smith had been placed in a learning-disabled class in school and dropped out after seventh grade. At the time of Smith’s crime, testing found that he performed math at a kindergarten level, he spelled at a third-grade level and read at a fourth-grade level.
“His grade school records, which showed that on every measure he was two to four years below grade average, culminating in a diagnosis of mental retardation in the seventh grade,” Waxman said.
Waxman went on to describe lower court rulings in the case as “the faithful application of Alabama law.”
Associate Justice Samuel Alito expressed concern that a ruling for Smith would create greater confusion surrounding who is eligible for the death penalty and create “a situation where everything is up for grabs,” and spur additional appeals where expert witnesses may argue for and against an individual’s mental competence.
Supreme Court Justice Ketanji Brown Jackson, meanwhile, expressed skepticism toward Overing’s argument that IQ should be prioritized as the principal metric for determining if an individual is intellectually disabled.
“I appreciate that [IQ is] one of the ways in which science has determined that you can make such a showing, but we also have allowed for evidence related to adaptive functioning to be taken into account when looking at intellectual functioning,” Jackson said. “So, I think what you’ve done is shift this to be all about the IQ test in a way that is not supported by our case law.”
Brown cited an amicus brief filed with the court, led by the American Association of Intellectual and Developmental Disabilities, where disability organizations similarly argued against IQ testing as a singular methodology for establishing whether or not Smith has subaverage intellectual functioning.
“As an objective assessment, intelligence quotient (IQ) testing can provide a good estimate of intellectual functioning,” the brief reads. “However, IQ tests (and the scores obtained from them) have limitations. As this Court has recognized, IQ tests have inherent imprecision.”
“The existence of multiple IQ scores for an individual does not change the requirement for a complete analysis,” the brief continues. “Neither clinicians nor courts should treat the existence of multiple scores as an excuse to avoid the need for a clinically valid, complete analysis of those scores and of all the other information about the person’s intellectual functioning and adaptive behavior.”
Following the arguments, Alabama Attorney General Steve Marshall expressed his support for Overing and his hope that the Supreme Court would reverse the lower courts’ rulings.
“I think Alabama set forth compelling arguments for how courts can address the question of intellectual disability and make that determination about whether or not somebody is eligible for execution,” Marshall said in a social media video.
“We feel strongly that Alabama will be able to prevail and be able to carry out the sentence of justice in this case,” Marshall added.
Marshall argued in a Wednesday press-release that Smith’s defense failed to prove that he is intellectually disabled, describing lower court rulings as the “unjustified expansion of a limited exception for capital offenders who are truly intellectually disabled.”
“Today, we defended Alabama’s lawful sentence and the basic principle that facts – not ideology – must continue to guide constitutional law. Joseph Smith is not intellectually disabled. Five independent IQ tests placed him well above the legal threshold, and no amount of judicial creativity can change that,” Marshall said in a written statement.
“The Eleventh Circuit’s approach would require states to ignore clear evidence to indulge hypotheticals designed to delay a convicted capital murderer from accountability after 27 years,” the attorney general continued. “The people of Alabama have the right to enforce the punishment chosen by their laws and juries, and our team has presented a strong case before the Justices to hold the line against criminals who have committed heinous murders.”
Marshall expressed pride in Overing’s arguments before the court, which he said, “made unmistakably clear that Alabama’s capital punishment system is both lawful and essential to the enforcement of justice.”
“The stakes extend far beyond this case, and his exceptional arguments ensure that Alabama and our sister States can continue to uphold criminal justice and the rule of law for all Americans,” the attorney general stated.
The Supreme Court is expected to deliver a verdict in Hamm v. Smith by the end of June 2026.
