A federal execution planned for Friday is back on, after a federal appeals court overruled a lower court ruling that the federal government failed to obtain a legally required prescription for the lethal injection drug pentobarbital. On Wednesday, the only Native American on federal death row, 38-year-old Lezmond Mitchell, was put to death using the same drug, over the objections of the Navajo Nation. Barring another intervention by the courts, Keith Dwayne Nelson will be put to death this evening at a federal prison in Terre Haute, Indiana.