Under no circumstance can I condone state-sponsored murder. For me it has nothing to do with accuracy of verdicts in trials and the chance of making a mistake. The prospect of life in prison (where prisons can be of more use to society than if they were dead) is enough of a deterrent for any potential criminal that considers the consequences (not that I think many do), and for those that don't consider the consequences (think crimes of passion) the punishment is no deterrent.