Confidential Informant refers to a professional person who provides information to law enforcement, often on a one time basis; people who provide the police with information and remain anonymous.

A confidential informant (CI) is an individual who provides information about criminal activity to law enforcement agencies, typically in exchange for leniency in their own criminal case or monetary compensation. In psychology, the use of confidential informants is often studied in the context of criminal investigations, particularly in cases where police may be relying on information provided by CIs to obtain search warrants or make arrests.

Examples of the use of confidential informants in criminal investigations include cases involving drug trafficking, organized crime, and terrorism. CIs may be individuals who have firsthand knowledge of criminal activity, such as drug dealers or members of criminal organizations, or they may be individuals who have been recruited by law enforcement to gather information.

The use of CIs can be controversial, as there are concerns about the reliability of their information and the potential for abuse by law enforcement. Psychologists may study the psychological effects of serving as a confidential informant, including the potential for psychological trauma and the impact on the informant's relationships and social support networks.