On September 11, 2001, the heroism of hundreds of police and law enforcement personnel involved in rescue operations at the World Trade Center exemplified the ideal of a good cop. These heroes stand in stark contrast to some of their colleagues who engage in misconduct and even crime. What makes a good cop versus a bad cop? In this new edition, the author addresses this question, which has particular relevance at a time when law enforcement personnel are being asked to take part in "homeland defense" against terrorism. He uses examples such as the heroism of September 11, 2001, as well as some of the major police scandals, controversies, and crises of our time -- the trial of O.J. Simpson, the events at Ruby Ridge, the tragedy at the Branch Davidian compound in Waco, the beating of Rodney King, Amadou Diallo's death, and the sodomization of Abner Louima by Justin Volpe -- to explore the ethical standards that should govern police commands and individual officers. He describes the impact of the decline, even collapse, of social pressure in modern society and within some police departments on the side of morals, manners, and reputable conduct on police who face ever more complex demands, problems, and difficulties in carrying out their mission. A new chapter considers how the future of policing is affected by the altered context of a nation at war with terrorism. How do we prevent our expectations -- and any new demands we may impose -- from undermining the capacity of police departments to protect the public from threats to public safety and from crimes that have nothing to do with terrorism? The author discusses recruiting and training standards for police and law enforcement personnel and whether these should be changed because of new domestic threats. He covers questions about the use of profiling and application of existing laws about intelligence gathering in counter terrorism. He also calls on federal agencies to provide police with more information and intelligence so that they can determine how best to apply their assets to protection and instruction of the public.