By Bill Cotterell
TALLAHASSEE, Florida (Reuters) - Florida prison officials on Tuesday carried out what they described as the first execution in the United States using the sedative midazolam hydrochloride in a lethal injection.
Midazolam was pumped into William Happ, 51, as the first of three drugs in a lethal injection cocktail designed to induce unconsciousness, paralysis and death by cardiac arrest, the Florida Department of Corrections said.
He was pronounced dead at 6:16 p.m. EDT in the execution chamber at the Florida State Prison in Starke and there appeared to be no suffering or unusual reaction stemming from the use of the new drug, department spokeswoman Misty Cash said.
In a hand-written final statement, Happ confessed to killing 21-year-old Angie Crowley, who was raped and murdered in 1986. He also apologized to those who believed in his innocence.
"It is to my to agonizing shame that I must confess to this terrible crime," he wrote.
Like many other death penalty states across the country Florida is running out of pentobarbital, a barbiturate that has long been the first of three drugs administered in a lethal injection "protocol" for executions.
Supplies of pentobarbital are low because its manufacturer has clamped down on sales of the drug for executions, prison officials said. Just last week, Missouri postponed an execution set for October 23 due to uncertainty about using a different drug, propofol, as a pentobarbital substitute.
Legal experts had voiced concern over whether midazolam, commercially known as Versed, would spare Happ from suffering extreme pain when the second and third drugs were administered.
Richard Dieter, executive director of the Death Penalty Information Center in Washington, called the use of the drug in an execution "an experiment on a living human being."
No late appeals were filed on behalf of Happ, who was sentenced to death in 1989 and abandoned his appeals in September.
Another Florida death row inmate, Etheria Jackson, has a hearing scheduled in Jacksonville federal court November 6, contending that the use of midazolam might violate the U.S. Constitution's ban on "cruel and unusual punishment" by allowing inmates to suffer in their final minutes.
Cash told Reuters state authorities had been satisfied that the new drug represented a humane replacement for pentobarbital, however, and would not open the door to "unnecessary or wanton infliction of pain and suffering."
"The department was required to develop a new protocol because we have limited supplies of pentobarbital sodium that will expire at the end of November 2013," Cash said.
(Editing by Tom Brown and Bob Burgdorfer)