When the people of California overwhelmingly voted for the 1994 "three strikes" law, many had no idea what they were approving. The official ballot argument in favor of what Newsweek called "the toughest law in the nation" kept it simple: "Three strikes keeps career criminals who rape women, molest children and commit murder behind bars where they belong." What few people realized, however, was that the sweeping nature of the law would put thousands of nonviolent men and women in prison for twenty-five years to life, for crimes as minor as shoplifting $2.69 worth of AA batteries,...