By David Beasley
ATLANTA (Reuters) - Georgia is scheduled to execute a two-time murderer on Monday in the state's first lethal injection using one drug instead of three, a switch the condemned inmate's lawyers are challenging as being too abrupt.
Warren Lee Hill, 52, was sentenced to death for fatally beating another inmate in 1990 while serving a life sentence for killing his girlfriend by shooting her 11 times.
Georgia delayed Hill's execution last week as it announced the switch from a three-drug cocktail that included the sedative pentobarbital to pentobarbital alone. The drug is sometimes used to euthanize animals.
Georgia officials did not say what prompted the change to the single drug. But in a legal challenge filed on Friday, Hill's attorney, Brian Kammer, said Georgia's supply of pancuronium bromide - one of the three drugs previously used in lethal injections - expired on July 1.
Kammer argued corrections officials did not give the required notice under state law of the change, depriving his client adequate time to review the new procedure.
Texas last week carried out its first execution using only pentobarbital because a supply of another drug was no longer available.
Arizona, Idaho, Ohio and Washington also have used a one-drug protocol in executions, and Missouri and South Dakota have announced plans to do so, according to the nonprofit Death Penalty Information Center.
Richard Dieter, the center's executive director, said the single drug results in a slower death but is potentially less painful than the three-drug cocktail.
"Defense lawyers and medical experts have been saying this is preferable, but a state has to be ready for the change," Dieter said.
Hill's execution, scheduled for 7 p.m. local time on Monday, would be the 25th this year in the United States, the center said.
Hill was serving a life sentence for the shooting death of his girlfriend, Myra Wright, when he killed a fellow prisoner, Joseph Handspike, in August 1990 by beating the man to death while he slept.
Hill did not request a last meal and will be offered the prison's regular meal of beef and bean burritos, steamed rice, salsa, corn, collard greens, cookies and fruit punch, the Georgia Department of Corrections said.
Hill's lawyers have argued that his execution should be halted because he suffered from what they termed mental retardation.
(Editing by Colleen Jenkins and Cynthia Osterman)