Editor's note: The U.S. Supreme Court order delaying the executions of three inmates challenging Oklahoma's lethal injection protocol leaves open the possibility that executions could proceed if the state obtains a substitute chemical, The New York Times reports. The order barred Oklahoma from executing the inmates with the controversial sedative midazolam. - Stephanie
Several U.S. states have been seeking alternative lethal injection compounds since the European Union barred German and Danish drugmakers from selling sodium thiopental, an anesthetic commonly used in lethal injections, to U.S. prisons in December 2011, says Jennifer Moreno of the Death Penalty Clinic at the University of California School of Law. The lone U.S. supplier, Hospira, stopped making the drug in early 2011.
Pentobarbital, a barbiturate used in euthanizing house pets, is considered a controversial alternative to sodium thiopental because it is little-regulated and, if contaminated, can cause extreme pain. In Missouri, state legislator John Rizzo wants all executions halted until it's determined whether the drugs come from pharmacies not licensed in Missouri.