Joseph Clifton Smith, sentenced for murder on Oct. 16, 1998

WASHINGTON −More than two decades after the Supreme Court said inmates who are intellectually disabled can't be executed, the court will consider how to deal with multiple intelligence tests in evaluating close calls.

The court on June 6 said it would take up the case of Alabama death row inmate Joseph Smith, who was convicted and sentenced to death for a brutal murder in 1997.

Smith’s IQ scores have ranged from 72 to 78.

Because IQ tests have an error range, lower courts said Smith’s IQ could be below 70, one of the factors for defining intellectual disability.

But the state argues that when five test scores are all above 70, it’s unlikely that Smith’s IQ is 70 or below.

The Justice Department similarly told the Supreme Court that some lower courts are confused about how to evaluate multiple IQ tests under Supreme Court rules for what counts as cruel and unusual punishment under the Eighth Amendment.

"That confusion prevents states from implementing lawful capital punishment," lawyers for the Justice Department wrote in a brief urging the court to get involved.

Lawyers for Smith countered that the Supreme Court has previously said there’s no precise math equation for determining an intellectual disability.

Supreme Court previously considered Smith's case

This isn’t the first time the high court has considered a request from Alabama to take up Smith’s case.

After sitting on the case for more than a year, the court in November ordered the Atlanta-based 11th U.S. Circuit Court of Appeals to clarify why it backed the trial judge’s determination that Smith is intellectually disabled and can’t be executed.

In a brief opinion, the court said it couldn’t tell if the appeals court used a holistic approach to weighing the evidence about Smith's disability or relied primarily on his lowest-possible IQ score.

The justices noted that the Supreme Court hadn't previously said how courts should evaluate multiple IQ scores.

In response, the appeals court said it considered the entire record.

Other factors considered besides IQ tests

In addition to IQ, other factors that define intellectual disability are “significant or substantial deficits in adaptive behavior” and the onset of those qualities before age 18.

“Clinicians who attempt to diagnose whether an individual has significantly subaverage intellectual functioning do not limit themselves to IQ tests,” the appeals court wrote.

Multiple IQ tests with similar results are not sufficient, the court said, because the test itself may be consistently flawed or improperly given.

On death row for brutal 1997 murder

Smith was convicted and sentenced to death for the 1997 murder of Durk Van Dam, who received 35 blunt force injuries and wounds from a saw on his neck, shoulder and back.

U.S. District Judge Callie V. S. Granade called the evaluation of Smith’s mental functioning a “close case” but wrote “the evidence indicates that Smith’s intelligence and adaptive functioning has been deficient throughout his life.”

This article originally appeared on USA TODAY: Supreme Court to consider use of multiple IQ tests in determining death penalty

Reporting by Maureen Groppe, USA TODAY / USA TODAY

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