The U.S. Supreme Court has for now cleared the way for states to use foreign sources in obtaining a lethal injection drug used in carrying out the death penalty.

Although the Supreme Court has upheld death by lethal injection, the regimen it has approved includes injection with a dose of sodium thiopental that is approved by the Food and Drug Administration to render the prisoner unconscious so he does not feel pain. In recent months, Hospira Inc., the only U.S. manufacturer of the drug, has been unable to meet demand, citing unspecified problems with its raw material suppliers. The shortage has left death penalty states scrambling to find alternatives.

Enter Arizona and the case of Jeffrey Landrigan. Landrigan's lawyers sought to block his execution because state officials would not say where they were getting the drug for the execution, and defense lawyers contended that there was no way to evaluate the safety of the drug without knowing where it came from. Pressed by a federal judge, the state admitted it was using a drug from a foreign country, but wouldn't specify which one.