what are us marshals used for?
<answer> The U.S. Marshals Service is responsible for ensuring the protection and safety of witnesses who testify in federal court. <context> Witness Security – The U.S. Marshals Service is responsible for ensuring the protection and safety of witnesses who testify in federal court. They have provided protection services for more than 8,000 witnesses since 1971, which includes protecting and relocating witnesses and providing them with new identities.