US Marshal

A United States Marshal was a law enforcement officer in the United States of America on Earth.

Wyatt Earp, who participated in the famous gunfight at Tombstone, Arizona served as a U.S. Marshal. (TOS episode Spectre of the Gun).

While participating in the Ancient West Program, Worf asked his son Alexander Rozhenko what was to be done with Eli Hollander - whom they had just arrested. Alexander, playing the role of deputy responded that they were to hold Hollander until the marshal from Rapid City could travel to Deadwood and take Hollander back to Rapid City for trial. (TNG episode A Fistful of Datas).