What’s the difference between a marshal and a sheriff?
Traditionally in the Old West, the sheriff was an elected county official. Towns elected or appointed marshals and also constables. A U.S. marshal was a federal appointment and covered outlaws who broke federal laws. A federal marshal (or deputy) could also pull double duty as a sheriff, sheriff’s deputy, town marshal or deputy marshal.
Towns that were county seats, like Tombstone, would have both a county sheriff and a town marshal. During the Cochise County War in the early 1880s the animosity between Sheriff John Behan and town Marshal Virgil Earp was a serious detriment to good law enforcement.