The Supreme Court early Thursday cleared the way for a second federal execution in as many days. The vote to allow the execution of Wesley Ira Purkey to go forward was 5-4, with the court’s four liberal members dissenting. Justice Sonia Sotomayor wrote that “proceeding with Purkey’s execution now, despite the grave questions and factual findings regarding his mental competency, casts a shroud of constitutional doubt over the most irrevocable of injuries.”