Lethal-Injection Drug Is Scrutinized

Midazolam, Used in Botched Oklahoma Execution, Tied to Two Other Cases Seen as Troubling.

Anesthesiologists say midazolam works like a dream. A few milligrams of the sedative calms patients’ preoperative anxiety, while leaving them alert enough to talk with doctors and nurses before the more potent drugs kick in.

Reviews of its newer role as part of states’ lethal-injection protocols aren’t as unanimous.

The drug, made by several companies in the U.S., has come into the spotlight with April’s high-profile botched execution in Oklahoma, the first in that state to use midazolam. State officials injected Clayton Lockett, convicted of kidnapping and murdering a 19-year-old woman, with 100 milligrams of midazolam to render him unconscious. They then injected another drug to paralyze him and a third to stop his heart.

According to witnesses, Mr. Lockett initially appeared to lose consciousness, but shortly thereafter began to writhe and mumble and lift himself up. Forty minutes later, he died of an unintended apparent heart attack, after officials halted the procedure. A spokesman for the Oklahoma Department of Corrections said that Mr. Lockett apparently suffered “vein failure,” making it hard to administer the drugs.

In recent weeks, some states have moved to bring back execution methods phased out years ago. Tennessee last month passed a bill to revive the electric chair as a possible execution method in the event that lethal injection becomes unworkable. Officials elsewhere have proposed bringing back gas chambers or firing squads as alternatives to lethal injection.

But many others are staying with injections as their sole execution method, even with largely untested drugs like midazolam.

The drug has been used in nine executions since last fall, and lethal-injection experts have voiced concerns about three of those—the Oklahoma case, one in Florida and another in Ohio.

In the past, executioners would typically use thiopental and pentobarbital, which belong to a class of drugs known as barbiturates. Anesthesiologists say thiopental, which has largely been phased out of use, was aimed mostly at preventing a patient from feeling stimuli that would typically be painful. Pentobarbital is still used, they say, mostly to induce comas.

The makers of thiopental and pentobarbital, worried about the drugs being associated with capital punishment, cut back their availability for executions, leading some states to turn to midazolam. It belongs to a drug class known as benzodiazepines, which anesthesiologists say are most often used to sedate or calm patients, not anesthetize them. Anesthesiologists say they typically administer midazolam to a patient only a few milligrams at a time and therefore know little about the effects of much larger doses, like those given in lethal-injection protocols.

There is little agreement about how much to use in executions. Florida uses 500 milligrams, while Oklahoma used 100 milligrams on Mr. Lockett. Ohio used only 10 milligrams of midazolam in a January execution, but in April announced that it would change to 50 milligrams.

“It’s uncharted territory,” said David Waisel, an anesthesiologist at Boston Children’s Hospital who has testified on behalf of death-row inmates. “States literally have no idea what they’re doing to these people.”

Some legal experts say the protocols using midazolam likely violate the Eighth Amendment to the U.S. Constitution, which, the Supreme Court has ruled, bans procedures that pose a “substantial” or “objectively intolerable” risk of “serious harm” when compared with “known and available alternatives.”

Others argue the Constitution doesn’t outlaw pain in executions or demand that execution methods always be foolproof.

“What the founders wanted to outlaw was gratuitous and intentional suffering,” said John McAdams, a political-science professor at Marquette University who has written on the death penalty.

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