The Criminal Investigations Branch (CIB) is dedicated to the mission of preventing, investigating and detecting criminal activity, and to apprehend violators of law. The first documented use of plainclothes officers on the Force occurred in1931. At that time plainclothes officers were assigned to areas with a high incidence of criminal activity, with special emphasis on larceny from automobiles and indecent exposure “and other offenses usually covertly committed when police are thought to be elsewhere.” Throughout the 1960’s the Unit responsible for preventing and investigating crimes was called the “Crime Prevention Division.” In 1970 the Unit’s name was changed to the Criminal Investigations Branch, and consisted of 3 sections; the Criminal Investigations, Tactical and Youth sections. In 1973 the Identification Section was established to ensure that crime scenes were properly processed. The Narcotics and Vice Unit was added to the Criminal Investigations Branch in 1983 to help battle the rising tide of drug violence and abuse in and around the parks in our nation’s capitol. Finally, in 2001 an Environmental Crimes Unit was added to the Criminal Investigations Branch to ensure these crimes against the environment received the attention they deserved.

Today, CIB consists of detectives, plainclothes investigators, identification technicians, and civilians, assigned to one of the following elements: Major Crimes, Identification Section, Special Investigations, Narcotics and Vice, and Environmental Crimes. The officers and members of the Branch are responsible for a complete and thorough investigation of serious incidents, e.g., deaths, sexual assaults, robberies, assaults, narcotics violations, and significant incidents in which a tort claim may be made against the United States Government. Personnel assigned to this Branch also provide presidential and dignitary protection, and assist in mass arrest situations and demonstrations and special events. On occasion members are detailed to local and Federal task forces created to combat specific types or incidents of crime.