The United States Marshals Service (USMS) is a United States federal law enforcement agency within the United States Department of Justice (see 28 U.S.C. § 561). The office of U.S. Marshal is the oldest federal law enforcement office in the United States created by the Judiciary Act of 1789. It assumed its current name in 1969.
The Marshals Service is part of the executive branch of government, and is the enforcement arm of the United States federal courts. The U.S. Marshals are responsible for the protection of court officers and buildings and the effective operation of the judiciary. The service also assists with court security and prisoner transport, serves arrest warrants, and seeks fugitives.