The Federal Bureau of Investigation (FBI) is the primary investigative arm of the United States Department of Justice (DOJ), serving as both a federal criminal investigative body and a domestic intelligence agency. At present, the FBI has investigative jurisdiction over violations of more than 200 categories of federal crimes, making the FBI the de-facto lead law enforcement agency of the United States government. The motto of the bureau is "Fidelity, Bravery, Integrity".
The FBI headquarters is in Washington, D.C., but they have a branch office at 26 Federal Plaza in New York City. The Irish mob of South Boston actually managed to have a mole in the FBI, unlike anything the Italian Mafia could achieve.