British police enjoy an international reputation for being one of the most ethical law enforcement institutions in the world. Domestically, however, their good standing has been shaken. Recent years have seen both individual officers, and sometimes entire forces, besieged by scandals and exposed as incompetent or corrupt. From spying on the grieving families of victims of crime and fathering children while undercover to ignoring and covering up child abuse and maliciously persecuting well-intentioned whistle-blowers, the range of unethical practices is broad.1 This article discusses how the recent drive to professionalize the police service of England and Wales presents opportunities for police leaders to address ethical failings and promote higher standards in the forces. Drawing on real examples from recent U.K. experience, it examines the role and potential of codes of ethics as tools of resistance against unreasonable government policy and considers measures designed to encourage and protect whistle-blowers.