This book provides an examination of noble cause, how it emerges as a fundamental principle of police ethics and how it can provide the basis for corruption. The noble cause - a commitment to "doing something about bad people" - is a central "ends-based" police ethic that can be corrupted when officers violate the law on behalf of personally held moral values. This book is about the power that police use to do their work and how it can corrupt police at the individual and organizational levels. It provides students of policing with a realistic understanding of the kinds of problems they will confront in the practice of police work.