OKLAHOMA CITY (CN) - Nine months after the botched execution of Clayton Lockett caused outrage and halted executions in Oklahoma, the state resumed lethal injections on Thursday.
Charles Warner, 47, died at 7:28 p.m., according to Oklahoma Department of Corrections spokeswoman Terri Watkins.
Warner was convicted in 1999 of the rape and murder of Adrianna Waller, the 11-month-old daughter of his girlfriend.
"Before I give my final statement, I'll tell you they poked me five times," Warner said before he was executed, according to The Associated Press. "It hurt. It feels like acid ... I'm not a monster. I didn't do everything they said I did."
Warner showed no obvious signs of distress as the first drug was administered, but said "my body is on fire." Witnesses said Warner twitched from his neck three minutes after the injection began, lasting for seven minutes until he stopped breathing. He died after 18 minutes.
Warner's execution was delayed for an hour as prison officials awaited word from the U.S. Supreme Court on his application for a stay. In a 5-4 ruling, the court declined to rule on whether the sedative midazolam would make him unconscious during the execution.
Warner unsuccessfully argued that the state's replacement three-drug execution cocktail would subject him to unconstitutional pain and suffering.
Several states have resorted to replacement execution drugs due to shortages of traditional drugs caused by anti-death penalty activists successfully asking large drug manufacturers to stop making them.
Oklahoma officials introduced an updated execution protocol in September that greatly increased the dosage of midazolam. The change was made after Gov. Mary Fallin ordered an investigation after Lockett's execution in April.
Witnesses said Lockett writhed in apparent agony, clenched his teeth and strained to lift his head after being injected with the sedative. Prison officials halted the execution at 20 minutes after running out of execution drugs.
Execution team members told state investigators that the execution chamber was a gruesome "bloody mess" due to attempts to tap a second femoral intravenous line in Lockett's groin.
In a strongly worded dissent, Justice Sonia Sotomayor said she was "deeply troubled" by evidence indicating the use of midazolam is not constitutional. She cited medical expert affidavits filed by Warner with the 10th Circuit and "a number of scientific studies" that said there is a "ceiling affect" with the drug, indicating electrical activity in the brain is not further diminished with larger doses.
Sotomayor noted that Lockett was able to regain consciousness after receiving enough of the drug "supposedly sufficient to knock him out."
"Given the evidence before the district court, I struggle to see how its decision to credit the testimony of a single purported expert can be supported given the substantial body of conflicting empirical and anecdotal evidence," Sotomayor wrote in the 8-page dissent. "I believe that we should have granted petitioners' application for stay."
Sotomayor said the increasing reliance on new, "scientifically untested" execution methods by states make such questions "especially important."
"Petitioners have committed horrific crimes, and should be punished," she wrote. "But the Eighth Amendment guarantees that no one should be subjected to an execution that causes searing, unnecessary pain before death. I hope that our failure to act today does not portend our unwillingness to consider these questions."
Justices Elena Kagan, Stephen Breyer and Ruth Bader Ginsburg joined the dissent.
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