The US Coast Guard has five police departments, and each of the departments is very small, something like 12 officers each.
The Police Departments are staffed by USCG Officers and Petty Officers who have undergone specialized police training.
The five departments are located at:
USCG Base Kodiak Alaska
USCG Training Center Cape May, New Jersey
USCG Training Center Petaluma, California
USCG Yard Baltimore, Maryland
US Coast Guard Academy, New London, Connecticut
US Coast Guard Academy, New London, Connecticut