A Special Agent, in the United States, is usually a criminal investigator or detective for a federal or state (and to a lesser degree county) government, who primarily serves in investigatory positions. Additionally, many federal and state "Special Agents" operate in "criminal intelligence" based roles as well. Within the US federal law enforcement system, dozens of federal agencies employ federal law enforcement officers, each with different criteria pertaining to the use of the titles Special Agent and Agent.
In federal/military intelligence usage, "agent" also refers to a human source or h...
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