The United States Marshals Service is a federal law-enforcement agency within the United States Department of Justice established for fugitive operations, the protection of federal officers and the management of criminal assets.
One of the Marshals waited for Tony Stark outside of Stark Expo. When Stark and Happy Hogan approached, she attempted to serve Stark with a subpoena to appear in Washington, D.C. before a Congressional committee headed by Senator Stern. Stark refused to take the envelope forcing Hogan to do it for him.
Because of Mariah Dillard's statement, Marshals Service was informed that true identity of Luke Cage is Carl Lucas, criminal who escaped from Seagate Penitentiary. Johnson and Franco were tasked to take him into custody. Marshals arrived to New York City and went to 29th Precinct Police Station where Lucas was. They then arrested Lucas for his unlawful escape and returned him to Seagate.
Marshals Service established supermax prison for enchanced individuals called Raft. Following conflict between Avengers in Schkeuditz, Sam Wilson, Clint Barton, Wanda Maximoff and Scott Lang were held at the Raft under Marshals' watch. However, Steve Rogers managed to infiltrate Raft, neutralize all marshals and let his friends free.