Tennessee’s governor on Monday ordered a halt to all executions through the end of the year and opened an investigation into why the state had failed to properly test lethal injection drugs that were set to be used on a prisoner last month.
The execution of that prisoner, Oscar F. Smith, was halted about an hour before he was scheduled to be killed because the drugs were not tested for endotoxins, contaminants that could cause unforeseeable side effects if injected. The moratorium will temporarily delay the execution of Mr. Smith and four other men who had been scheduled to die this year.
The failure to test for the toxins, which experts said could cause respiratory failure or other distressing symptoms before death, was the latest in a string of errors and challenges for states seeking to carry out the death penalty as they find it harder to procure lethal drugs. A judge in Oklahoma is currently weighing whether a drug used during executions in several states, including Oklahoma and Tennessee, is constitutional, and South Carolina is preparing to carry out its first execution by firing squad after saying it could no longer acquire lethal injection drugs.
Gov. Bill Lee of Tennessee, a Republican, said on Monday that Ed Stanton, a former federal prosecutor in Tennessee, would lead an investigation into why the drugs used for lethal injection were not tested for the endotoxins.
Mr. Smith’s lawyers, who had called for a moratorium and investigation, welcomed the governor’s move.
“The use of compounded drugs in the context of lethal injection is fraught with risk,” Kelley Henry, the top death penalty lawyer in the Federal Public Defender’s Office in Nashville, said in a statement. “The failure to test for endotoxins is a violation of the protocol. Governor Lee did the right thing by stopping executions because of this breach.”
Dr. Harry Kochat, an expert in pharmaceutical science at the University of Tennessee Health Science Center, said that endotoxins are left behind when bacteria are killed and can quickly cause hypertension, respiratory failure and other catastrophic effects, depending on the dose.
“The moment the endotoxins get in, the first symptom that is often reported is a fever, and that can cause secondary infections and affect your organs,” Dr. Kochat said.
