Let us read it for you. Listen now. Your browser does not support the audio element. As a longtime death penalty abolitionist, I've often compared the death penalty in America to a train with no brakes: Once the machinery starts moving, it becomes extraordinarily difficult to stop.But the real problem is that the train should never have been built.Today, Alabama, Louisiana, Mississippi, Oklahoma, and Arkansas are experimenting with nitrogen gas executions, a method officials claim is more humane. But from noose to needle to nitrogen, our constant search for a more acceptable way to kill is a story of failure,...