Jailed Reincarnation

A prisoner is being executed by the military for committing a horrible crime. After spending his final day with his best friend and his wife, he steps up to the guillotine to accept his fate. As his execution is complete, the prisoner discovers he’s not quite dead but instead in the body of a newborn! What crime did the prisoner commit? Why did he commit it? What will he do when given a second chance to live?