A particularly compelling argument has recently come to my attention that warrants mention.
...We humbly suggest a solution at hand that can satisfy everyone: The Schiavo Method. We simply deprive the condemned man of all food and water until he dies. The New York Times and the courts have already determined beyond a shadow of a doubt that this treatment causes the patient no pain. If it was appropriate therapy for Mrs. Schiavo, who as far as we know never actually killed anyone, who could possibly think it was cruel or unusual to apply it to a condemned murderer?...I find this an absolutely compelling argument.