A one-stop resource for understanding historical and contemporary perspectives on ideological extremism in law enforcement, as well as its wider impacts on American society. The work blends narrative overview, biographies, essay perspectives, and a helpful guide to other resources to facilitate understanding of the contemporary problem of extremism in American law enforcement. Written by experts in the criminal justice field, the book focuses on the extent, motivations, causes, and dangers of ideological extremism in the ranks of America's police, from the smallest towns to the biggest cities. In addition, it discusses reforms that have been proposed—and in some cases implemented—to combat the problem, including measures introduced in other countries.