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Story highlights

Kenneth Williams' attorney calls for investigation over account that his body lurched

Williams, 38, was convicted of two murders

(CNN) —  

A lawyer for an executed Arkansas inmate called for an investigation over reports that his client convulsed during the lethal-injection process – casting fresh questions about a sedative that critics say has led to botched executions.

Williams, a convicted murderer, was executed Thursday night, one of four Arkansas inmates put to death in eight days. They and death row inmates nationwide had challenged executioners’ relatively recent use of the sedative midazolam – a drug that some states started using because manufacturers restricted access to other drugs.

Williams’ body violently lurched forward about three minutes after midazolam, the first of a three-drug cocktail, was injected at Arkansas’ Cummins prison, an Associated Press reporter who was there said.

The body jerked about 15 times across 10 or 15 seconds, before moving five more times at a slower rate, AP reporter Kelly Kissel said. Only midazolam had been injected at that point, Kissel said.

Williams’ attorneys singled out that drug. Death penalty critics have long argued that though midazolam is a sedative, it is not a painkilling anesthetic like drugs once commonly used, and that the condemned would feel tortuous pain from the drugs that come next.

“The accounts of the execution of Mr. Williams tonight are horrifying,” said his attorney, Shawn Nolan.

“We are requesting a full investigation into tonight’s problematic execution,” Nolan said.

The drug already was in the spotlight on another level in Arkansas. The state initially wanted to execute eight inmates this month because the state’s midazolam supply expires Sunday, and because Arkansas is unsure it can get another batch as drugmakers increasingly say they don’t want their products used in executions.

Williams and three others were executed from April 20 through Thursday. Courts postponed the other four executions for various reasons not relating to midazolam, and they will not be executed this month.

The arguments over drugs

To understand the controversy over midazolam, it’s helpful to explore why some states began using it – and what happened when they did.

Traditionally, many states used a three-drug cocktail for lethal injections: The first (sodium thiopental or pentobarbital) put the prisoner to sleep; the second (pancuronium bromide) brought on paralysis; and the final agent (potassium chloride) stopped the heart.

But manufacturers and European countries started withholding sodium thiopental and pentobarbital around 2010, saying they didn’t want them used in executions. Arkansas and at least six other states turned to midazolam as an alternative, the Death Penalty Information Center says.

In 2014, several executions with a protocol including midazolam were widely considered botched. In Ohio, Dennis McGuire gasped and convulsed for 10 minutes before dying. In Arizona, Joseph Wood snorted and gulped for air as he died over a period of two hours. And in Oklahoma, Clayton Lockett writhed for 43 minutes before succumbing to a heart attack.

Those states issued holds on capital punishment while the processes were reviewed.

Seeing this, lawyers for other inmates raised objections – that midazolam could not reliably render someone unconscious like a barbiturate like pentobarbital. They argued that would expose their clients to horrific pain from the heart-stopping agent, potassium chloride.

“Because of the way midazolam works in the human body, it could sedate an individual to the point where he was incapable of communication that he was in pain while doing nothing to suppress the experience of pain,” reads an unsuccessful lawsuit that had been filed on behalf of an Alabama inmate executed in 2016.

“Midazolam is a sedative. It makes you relax, but it has no pain-blocking qualities,” Dr. David Waisel, an anesthesiologist at Harvard Medical School, told CNN earlier this month.

In June 2015, the Supreme Court upheld the use of midazolam in executions in a 5-4 ruling.

Like others before them, Williams and the other seven inmates Arkansas wanted to execute this month initially fought their executions on the grounds that midazolam does not reliably prevent a painful death. The Arkansas Supreme Court denied the claim.

Arkansas: No indication Williams showed pain

Arkansas officials pushed back against notions that Williams showed awareness of pain.

Gov. Asa Hutchinson, explaining what the the state’s Department of Correction director told him about Williams’ body movements after midazolam was given, described it as “10 seconds of coughing without noise.”

“If you look at the package inserts for midazolam, you see one of the side effects is coughing,” he said, adding that Williams showed no indication of pain.

Little Rock TV anchor Donna Terrell, who also saw the execution, told CNN affiliate KARK that Williams’ chest started going up and down rapidly for a time after midazolam was administered, but Williams’ face was expressionless, and it didn’t appear as if he were in pain, she said.

Waisel has warned that if a patient isn’t fully sedated by midazolam, the second drug – the paralytic – could prevent observers from seeing what might otherwise be a reaction to the third, heart-stopping drug.

Executions elsewhere

Though execution drugs are harder to come by, and the number of annual US executions has dropped each year since 2009, capital punishment continues. Since 2010, 18 states have executed 270 inmates, according to the Death Penalty Information Center.

Midazolam was just one alternative that seven states turned to as the drug supply dried up. Other states used compounding pharmacies – which aren’t federally regulated – to manufacture pentobarbital. Others have devised a one-drug method.

In 2014, Tennessee said that when lethal injection drugs can’t be found, the state can use the electric chair. The next year, Utah successfully passed legislation to reintroduce firing squads.

Methods outside of lethal injections would be unusual. Since the Supreme Court reinstated the death penalty in 1976, 1,452 people have been executed in the United States – all but 175 by lethal injection, according to the Death Penalty Information Center.

The future of midazolam appears mixed. Regarding the states with the controversial 2014 executions:

Arizona: The state agreed in December not to use midazolam. Its new rules allow a number of options, including one dose of pentobarbital. But executions still are on hold until litigation in federal court is completed, the DPIC says.

Ohio: The state decided in October that it still could use midazolam in a three-drug formula, as one of several options. A judge issued an injunction blocking the use of midazolam, and a federal appeals court is set to hear the case in July.

Oklahoma: A panel this month recommended that Oklahoma continue its moratorium until significant reforms happen. One reform the panel suggested: Dropping midazolam and the three-drug protocol in favor of a single, lethal barbiturate.

But in Arkansas, the governor said Friday that he sees “no need to change the protocols,” citing the Supreme Court affirmation.

It’s unclear whether Arkansas will receive fresh midazolam supplies after its current batch expires. One manufacturer, West-Ward Pharmaceuticals, filed a brief in support of the eight inmates this month, saying it tries to ensure its medication isn’t used in executions.

CNN’s Ariane de Vogue, Faith Karimi, Dakin Andone, Eliott C. McLaughlin, Sarah Aarthun and Deborah Goldschmidt contributed to this report.