Whileconfidential informants (CI s)can play a crucial role in police investigations, they also have the potential to cause great harm ifthey are dishonest. The process by which police agencies qualify a CI to work and the strength of agency policy may be the source of the problem. This Brief examines the integrity problem involving CIs in police operations within the United States, provides an overview of pitfalls and problems related to veracity and informant integrity including the difficulties in detecting when a CI is lying, and compares the provisions of actual published police policy...