The supreme court in the southern US state of Georgia on Monday gave a temporary reprieve to a man sentenced to death for murder just two hours ahead of his scheduled execution.
Warren Hill was scheduled to be executed by lethal injection at 7pm (23.00 GMT) for killing a fellow inmate.
The 52-year-old African-American, who has spent the last 21 years on death row, reportedly has an IQ of 70, which puts him below the threshold for mental disability.
The US Supreme Court ruled against the execution of prisoners with mental disabilities in 2002, saying the disability “would run the risk of a wrongful execution.” However, the Court left each state with the authority to determine what constitutes mental disability.
Hill was to be the first person in Georgia to be put to death using a single drug, pentobarbital, instead of the previously standard three-drug cocktail.
The state supreme court ruled unanimously to grant a stay of execution, saying it needed to investigate whether a lower court erred in determining that the change in execution protocol was legal under Georgia law.
The court will offer its own ruling on whether the new execution method is legal, which could take weeks.
“Georgia, almost on the eve of the execution, switched to a different method, pretty radically different,” Death Penalty Information Centre director Richard Dieter told AFP.
There have been “only a handful of executions with this one drug,” he added, saying “if you want to use it, you need to know a lot more.”
The case also highlights questions over the severity of Georgia's criteria to define who is mental handicapped.
While Georgia requires proof of mental disability “beyond a reasonable doubt,” all 49 other states consider “a preponderance of evidence” enough proof.
The US Supreme Court had declined to review Hill's case, but his lawyers have requested they reconsider.
Monday, a source familiar with the matter said the Court will hold off on deciding whether to hear an appeal now that the execution has been postponed.
Georgia was “the first state to ban the death penalty for people with mental retardation,” Dieter said, but because it was first, it created “a very strict standard.”
He said the it should be up to the Supreme Court to decide the the norms and to “control the states that are outside” them.
Last week, a Georgia judge ruled that Hill was intellectually disabled to a lesser degree than the state requires to preclude the death penalty.
But “the problem is that Georgia makes the proof requirement essentially impossible to meet for defendants who clearly have mental retardation,” one of Hill's lawyers, James Ellis, told AFP.
Several high profile figures - including former US president Jimmy Carter, as well as the family of Hill's victim - have for Georgia to commute Hill's sentence to life in prison.
France and a UN human rights expert have also called for the execution to be suspended. - Sapa-AFP