Do You Have What It Takes to Be a Marine Criminal Investigator?

Marine criminal investigator agents have a variety of duties

U.S. Marines insignia
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Information from MCBUL 1200, parts 2 and 3.

One of the most competitive ratings (jobs) in the Marine Corps is the criminal investigation division (CID) agent. These agents work in the criminal investigation division (CID) and the Naval Criminal Investigative Service, or NCIS (which inspired the dramatic television show of the same name). 

The military operational specialty (MOS) code for this rating is 5821. 

Marine Corps CID agents conduct all general criminal investigations under the jurisdiction of the CID and NCIS, which includes conducting covert operations, interrogation of witnesses and crime scene investigations.

Marine CID agents are trained in hostage negotiations, provide personal protective services, administer polygraph exams, and work with other military civil and federal law enforcement agencies. 

They also provide guidance and supervision to junior CID agents and apprentice investigators and support both installation and Marine Air Ground task force commanders. The most common crimes they investigate include drug offenses, theft, and identity theft cases. But if asked to serve in support of units aboard ships, Marine CID agents could be tasked with investigating criminal activity at sea, including acts of piracy.

Requirements for Marine CID Agents 

In order to qualify for this job, recruits need a general technical score of at least 110 on the Armed Services Vocational Aptitude Battery (ASVAB) test, be 21 years old and have normal color vision. They need to have vision correctable to 20/20 and a valid state's drivers license. They have to be of strong moral character as defined by the Marine Corps and must be between 62 and 65 inches tall.

In addition, aspiring CID agents can't have a history of mental or emotional disorders, and can't have any convictions by special or general courts-martial or civil courts, with the exception of minor traffic violations. They can't have any nonjudicial punishment convictions involving illegal drugs or spouse abuse or domestic violence.

They'll need to complete a single scope background investigation (SSBI) and be able to qualify for a top-secret security clearance, with a satisfactory periodic review every five years. 

Training for Marine CID Agents

A minimum of six months on-the-job training in criminal investigative duties is required while still an apprentice investigator. Also required is a recommendation by the CID officer and provost marshal for assignment to the U.S. Army Criminal Investigation Division Apprentice Special Agent Course in the U.S. Army military police school, in Fort Leonard Wood, Missouri. Completion of this course is mandatory for CID agents. 

In addition, new criminal investigators assigned to NCIS as special agents must be determined eligible for duty by an NCIS screening board.

Additional training is required in order to be qualified as polygraph examiners and hostage negotiators.

Civilian Jobs Related to CID Agents

The U.S. Department of Labor lists two specific occupations as similar to Marine CID agents. They include detective and polygraph examiner. Within the Marine Corps, MOS 5821, criminal investigator and MOS 5822, polygraph examiner, are related to the CID agent role.