FOR over two decades, James Q. Wilson—whom Wall Street Journal columnist Paul Gigot recently called “the best social scientist in America”—has been teaching us how to think about crime and justice. In Crime,† Wilson has joined forces with Joan Petersilia, past president of the American Society of Criminology and former director of the Criminal Justice Program at RAND, to produce a collection of writings that transcends ideology (Wilson is conservative, Petersilia liberal) and is as comprehensive and authoritative as its ambitious title implies.