Warren Hill Execution
Warren Hill (Video still/CBS News)

ATLANTA (AP) — A 54-year-old man who has come within hours of execution three times in recent years is scheduled to die Tuesday evening unless the U.S. Supreme Court intervenes. Warren Lee Hill’s lawyers argue he shouldn’t be executed because he is intellectually disabled.

Warren Lee Hill is set to be put to death at 7 p.m. Tuesday at the state prison in Jackson, Georgia. Different courts have intervened with temporary reprieves at the last minute on three previous occasions.

State and federal courts have already rejected his filings this time around, and the State Board of Pardons and Paroles — the only entity authorized to commute his sentence to life in prison — denied him clemency Tuesday. Hill has filings pending before the U.S. Supreme Court, which is now the only potential barrier between him and a lethal injection of the drug pentobarbital.

“The clemency board missed an opportunity to right a grave wrong,” Brian Kammer, a lawyer for Hill, said in an emailed statement Tuesday. “It is now up to the U.S. Supreme Court to ensure that an unconstitutional execution of a man with lifelong intellectual disability is prevented.”

Hill was sentenced to serve life in prison for the 1986 killing of his 18-year-old girlfriend, who was shot 11 times. While serving that sentence, he beat a fellow inmate, Joseph Handspike, to death using a nail-studded board. A jury in 1991 convicted Hill of murder and sentenced him to death.

Lawyers for Hill have long argued he is intellectually disabled and, therefore, shouldn’t be executed. State law and a 2002 U.S. Supreme Court decision both prohibit the execution of the intellectually disabled.

But Georgia has the toughest-in-the nation standard for proving intellectual disability. It requires capital defendants to prove beyond a reasonable doubt that they are intellectually disabled in order to avoid execution on those grounds. The state has consistently said Hill’s lawyers failed to meet that burden of proof.

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