An untried cocktail of drugs was blamed for a botched execution in Oklahoma last night, after a man suffered an agonising 43-minute death in an execution by lethal injection.
Clayton Lockett was left writhing on a gurney 20 minutes into the execution, which was then halted before he died of a heart attack 23 minutes later.
The state was using an untried and controversial dosage of the sedative drug midazolam, which was also used by Ohio state in the January execution of Dennis McGuire, who took 25 minutes to die - the longest execution in that state since capital punishment resumed 15 years ago.
In this latest case at Oklahoma state penitentiary, a double execution was due to take place. Prisoner Charles Warner, who was due to be put to death immediately after Lockett at 8pm, had his execution postponed in wake of the failed attempt.
His lawyer Madeleine Cohen slammed the state's handling of the death. "After weeks of Oklahoma refusing to disclose basic information about the drugs for tonight's lethal injection procedures, tonight Clayton Lockett was tortured to death," she said.
Her client has had his execution rescheduled for two weeks' time, during which time investigators will have work out what exactly went wrong.
Prisoners Clayton Lockett, left, and Charles Warner, right (image: Kxan)
According to an eyewitness report in the Guardian, Lockett was pronounced unconscious 10 minutes into his execution last night. But three minutes later, he started writhing about violently and groaning as he lifted his head and shoulders from the gurney. His legs moved and he was heard to utter the word "man" at 6.39pm - 16 minutes into his execution.
Prison guards then drew the curtains of the chamber from the public viewing gallery and halted the execution but Lockett later suffered a heart attack and was pronounced dead at 7.06pm.
Prison officials said that after they realised the drugs were not having the expected effect on Lockett, they discovered that one of his veins had ruptured.
"We believe that a vein was blown and the drugs weren't working as they were designed to. The director ordered a halt to the execution," spokesman Jerry Massie said.
The gruesome incident is likely to revive the debate over use of untried drugs by US death penalty states, who have been forced to look for new drug methods in executions in the wake of an increasing cut-off from European-based pharmaceutical suppliers opposed to capital punishment.
A gurney used for lethal injections in the US
Oklahoma state decided to lethally inject both Lockett and fellow convict Warner with midazolam followed by vecuronium bromide and potassium chloride, in a dosage never used before at a US execution.
A corrections spokesman had previously warned the executions would probably take longer than normal because the first drug was expected to work more slowly.
The proposed cocktail triggered a storm of controversy among lawyers and politicians, with some accusing the state of secrecy and non-transparency in its sourcing of the drugs. Both prisoners had unsuccessfully challenged an Oklahoma state law that blocks officials from revealing the identities of the companies supplying the drugs.
Amid the furore, their executions had been stayed but this decision was overturned by Oklahoma's supreme court.
"This is exactly why we fought so hard to get this information known not just for our clients but for everyone," said Lockett's lawyer, Susanna Gattoni. "This shouldn't be kept secret. This is unfortunately what happens."
"It was a horrible thing to witness. This was totally botched," she added.
The state of Ohio used midazolam with a different drug, the painkiller hydromorphone, in the January execution of McGuire. He took 25 minutes to die after being injected with the untried cocktail of drugs and appeared to be gasping for breath at points, witnesses reported at the time.
A review carried out by the prison concluded he had not suffered any distress, but the prison said it would increase the dosage of the injection the next time round.
Dennis McGuire, who took 25 minutes to die
The European manufacturer of the drug pentobarbital, which was previously used in US executions, has stopped allowing its supply for lethal injections. Ohio state began using midazolam and hydropmorphone instead, with other states trying out different combinations and dosages to compensate for the cut-off.
Richard Dieter, the executive director of the Death Penalty Information Center, which monitors capital punishment, said the latest botched execution could change public opinion and procedure on the use of lethal injections.
"This could be a real turning point in the whole debate as people get disgusted by this sort of thing," he told the Associated Press.
"This might lead to a halt in executions until states can prove they can do it without problems. Someone was killed tonight by incompetence."
Republican governor of Oklahoma, Mary Fallin, said she had ordered a review into Lockett's execution. She had previously pushed for both Lockett and Warner's executions to go ahead.
Lockett, 38, was sentenced to death in 1999 for shooting and burying alive a 19-year-old woman, and raping her friend in a home invasion. Warner, 46, was convicted of the 1997 murder and rape of an 11-month-old girl. McGuire, 53, was convicted of raping and stabbing to death a pregnant woman.
Words: Anna Brech, Photos: Rex Features