It is composed of civilian (GS-1811), active duty, reserve enlisted, and warrant officer special agents.

The mission of the Coast Guard Investigative Service (CGIS) is to conduct professional criminal investigations, engage in law enforcement information and intelligence collection, provide protective services, and establish and maintain law enforcement liaison directed at preserving the integrity of the Coast Guard, protecting the welfare of Coast Guard personnel, and supporting Coast Guard and Department of Homeland Security (DHS) maritime law enforcement and counter-terrorism missions worldwide.

This authority provides for Coast Guard special agents to conduct investigations of actual, alleged or suspected criminal activity; carry firearms; execute and serve warrants; and make arrests for all crimes under the jurisdiction of the United States.

The CGIS special agent workforce is composed of active duty military, reserve, and civilian personnel.

All CGIS Special Agents have full arrest powers under Title 14 section 95 of the United States Code.