A US federal appeals court has stayed the execution of a schizophrenic man just hours before he was scheduled to die in Texas by lethal injection.
Scott Panetti, who has suffered from the mental illness for three decades, was set to die for the 1992 shooting of his estranged wife's parents at point blank range.
The Fifth Circuit Court issued the decision, which cannot be appealed, in order "to allow us to fully consider the late arriving and complex legal questions at issue in this matter."
Panetti's lawyers requested more time so that psychiatric evaluation could be conducted to determine their client's criminal liability, an evaluation that they said had not been carried out in seven years.
Panetti won support for his case from the likes of the Mental Health America advocacy organization, psychiatrists, former judges, prosecutors and religious groups.
The case also garnered interest from the European Union, which urged Texas Governor Rick Perry to grant Panetti clemency.
"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," his lawyers Greg Wiercioch and Kathryn Kase said in a statement.
"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," they said.
At the trial, Panetti acted as his own attorney, wore a cowboy outfit and tried to call the pope, John F. Kennedy and Jesus as witnesses. He was convicted in 1995.
Panetti had been scheduled for execution at 6:00 pm (00H01 Thursday) at the state penitentiary in Huntsville, Texas.
Neither the Supreme Court nor Perry had yet weighed in on the appeal.
The stay was issued by the Fifth Circuit under a statute allowing it to preserve its jurisdiction over the case, and which prohibits appeal to any other body, according to Panetti's defense team.
Panetti has been hospitalized a dozen times for hallucinations and psychotic episodes.
Execution stayed for mentally ill prisoner