The Supreme Court is expected to declare any day whether the injection of a drug called Midazolam violates the Eighth-Amendment protection against cruel and unusual punishment. Given the difficulty of procuring other suitable drugs, states devoted to the death penalty are lining up alternative ways to efficiently end human life. In Oklahoma (48 prisoners on death row), the answer seems to be nitrogen gas, a method favored by some proponents of assisted suicide but not something that has been employed in an execution chamber. Utah (nine on death row) proposes to revive the firing squad. Tennessee (67 on death row) is preparing to fire up its electric chair. Decisions, decisions. The Marshall Project took a closer look at the thinking that goes into the logistics of execution.