Nitrogen gas was just used for the first time to execute a prisoner on death row. The execution of Kenneth Smith does not answer the many questions raised by this new means of capital punishment. Is it “perhaps the most humane method” of execution,” as the Alabama attorney general has claimed? Or is it cruel and unusual punishment, as Smith’s attorneys and others have argued? Answering these questions is of vital importance, since nitrogen gas has been approved by three states for capital punishment.