Attorneys for convicted murderer Duane Owen on Monday asked the U.S. Supreme Court to block his execution, after Florida courts rejected arguments that he was not mentally competent to be put to death.

With Owen scheduled to face lethal injection Thursday at Florida State Prison, his attorneys requested that the U.S. Supreme Court issue a stay of execution and contended that he "lacks a rational understanding of the connection between his crime and [the] impending execution due to his fixed psychotic delusions and dementia."

Along with a stay, the attorneys want the U.S. Supreme Court to order briefing about the issues or to send the case back to the Florida Supreme Court. The arguments are based on the U.S. Constitution's Eighth Amendment, which bars cruel and unusual punishment, and legal precedents that prevent executing people who are not mentally competent.

"Florida has a minimal interest in finality and efficient enforcement of judgments, but Owen, whose delusions and dementia prevent him from rationally understanding the consequences of his execution, has a right in ensuring that his execution comports with the Constitution," one of the documents filed Monday said. "This right includes the ability to have meaningful judicial review of the complex constitutional claims he timely raises."

Attorneys for the state had not filed responses as of late Monday afternoon, according to a U.S. Supreme Court online docket.

But the Florida Supreme Court issued two opinions last week that refused to halt the execution. One of the opinions upheld a ruling by a Bradford County circuit judge who concluded that Owen was "feigning or malingering psychopathology to avoid the death penalty."

"Mr, Owen is aware that the state is executing him for the murders he committed and that he will physically die as a result of the execution," Circuit Judge James Colaw wrote in the June 4 ruling, after holding a hearing that included expert testimony. "There is no credible evidence that in his current mental state Mr. Owen believes himself unable to die or that he is being executed for any reason other than the murders he was convicted of."

Gov. Ron DeSantis on May 9 signed a death warrant for Owen, 62, in the murder of Georgianna Worden, who was bludgeoned with a hammer and sexually assaulted in her Boca Raton home in May 1984, according to the death warrant and court records.

Owen also was sentenced to death in the March 1984 murder of 14-year-old Karen Slattery, who was babysitting at a Delray Beach home, according to court documents. Slattery was stabbed to death.

Colaw is a judge in the North Florida circuit that includes Florida State Prison.

If the execution is carried out Thursday, Owen would be the fourth Florida inmate put to death in less than four months.

The state on May 3 executed Darryl Barwick in the 1986 murder of a woman in her Panama City apartment. That followed the April 12 execution of Louis Gaskin in the 1989 murders of a couple in Flagler County. The state on Feb. 23 put to death Donald David Dillbeck, who murdered a woman in 1990 during a carjacking in a Tallahassee mall parking lot.

Dillbeck was the first person executed since Gary Ray Bowles was put to death by lethal injection in August 2019 for a 1994 murder in Jacksonville.

Jim Saunders reports for the News Service of Florida.

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