WASHINGTON -- Less than 12 hours before the state of Texas was set to execute Scott Panetti, an appeals court issued a stay Wednesday morning, meaning Panetti's lawyers will have another chance to argue that the death penalty is unconstitutional in their client's case.

Panetti, 56, is on death row for the 1992 murder of his in-laws, whom he killed while his wife and daughter were watching. He has suffered from schizophrenia and other mental illnesses for over 30 years and been hospitalized more than a dozen times.

The execution was scheduled for 6 p.m. CST Wednesday. Panetti's supporters have argued that his sentence should be commuted to life in prison because putting him to death would violate the Eighth Amendment, which bars cruel and unusual punishment.

Now, Panetti's lawyers will have another opportunity to argue their case. As BuzzFeed reported, the 5th U.S. Circuit Court of Appeals issued a stay of execution Wednesday morning "to allow us to fully consider the late arriving and complex legal questions at issue in this matter." The court said it will be setting a schedule for oral arguments soon.

"We are grateful that the court stayed tonight’s scheduled execution of Scott Panetti, a man who has suffered from schizophrenia for three decades, for a careful review of the issues surrounding his competency," said Gregory W. Wiercioch and Kathryn M. Kase, Panetti's attorneys, in a statement Wednesday.

"Mr. Panetti's illness, schizophrenia, was present for years prior to the crime, profoundly affected his trial, and appears to have worsened in recent years. Mr. Panetti has not had a competency evaluation in seven years, and we believe that today's ruling is the first step in a process which will clearly demonstrate that Mr. Panetti is too severely mentally ill to be executed," they added.

The Texas Tribune reported on Monday that Kase and Wiercioch had asked the circuit court to intervene in the case, in addition to going to the U.S. Supreme Court. But the strongest pressure has been on Gov. Rick Perry (R). Unlike in other states, the Texas governor can't single-handedly commute a prisoner's sentence. Perry could, however, have ordered Panetti's execution to be delayed for 30 days so that a new mental health assessment could be conducted.

Panetti's case has attracted support from mental health reform advocates and death penalty opponents, as well as from a number of well-known conservatives. Former Texas Rep. Ron Paul and former Virginia Attorney General Ken Cuccinelli are among the conservatives who have been calling on Perry to step in.

"Texas was about to cross a line by executing a severely mentally ill man," said Mark Hyden, national coordinator for Conservatives Concerned About the Death Penalty, in a statement after the court's announcement. "A wide array of conservative and faith leaders have spoken out in record numbers about this case. We have made it abundantly clear that numerous conservatives and Evangelicals view executing those who are mentally ill as a violation of our values as Americans. Conservatives have demonstrated we are firmly part of what appears to be a national consensus against executing people who are mentally ill.”

Former Texas Gov. Mark White (D), who oversaw 19 executions while in office, has also said Panetti should not be killed.

"There are incredibly close and difficult calls that have to be made to either allow or prohibit the death penalty from being carried out," said White. "But Scott Panetti's plea for clemency is no such case. He is a severely mentally ill man. His trial was a sham. And executing Panetti would say far more about us than it would about the man we are attempting to kill."

During his trial, Panetti represented himself while wearing a purple cowboy costume. He tried to subpoena more than 200 witnesses, including John F. Kennedy and Jesus Christ. Prosecutors have suggested that Panetti is faking his illness.

Wiercioch and Kase have been especially upset about the way they found out their client's execution date. A judge signed an order on Oct. 16 of this year that set Panetti's execution date for Dec. 3, but the district attorney never notified the lawyers that their client had been scheduled to be put to death. Instead, they learned about the pending execution on Oct. 30, through an article in the Houston Chronicle.

"Fourteen days passed during which counsel could have been investigating the issues surrounding Mr. Panetti’s competence -- issues which the District Attorney surely knew would have to be litigated to ensure that Mr. Panetti’s execution would not violate the Eighth Amendment," Wiercioch and Kase wrote in a letter to Perry Monday, in which they requested a 30-day delay.

This is a breaking news story and will continue to be updated.

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