Profile of Criminal Investigators, Part 1: Army and Marines

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Military Police (MPs) may investigate crimes at bases and installations, but some crimes require the detective's touch. Each branch of service has its own methods and job designations for criminal investigations, but all are Federal law enforcement officers. In addition to investigating felonies and other major crimes involving the military at home, military criminal investigators coordinate with other Federal law enforcement agencies and even handle war crimes and antiterrorism missions abroad.

Owing to their similarity, in this article we'll discuss the Army and Marine Corps Criminal Investigation Divisions (CID).

Common Requirements

Enlisted CID Agents in both the Army and Marine Corps may only be recruited from those currently serving, but neither specialty necessarily requires you to hold an MP Military Occupational Specialty (MOS) to be selected. Whether soldier or Marine, you absolutely must be a US citizen, at least 21 years old, have normal color vision, a driver's license, and excellent oral and written communication skills.

Not surprisingly, both branches also require Top Secret clearance eligibility and ban those with a criminal record (aside from traffic violations), emotional and psychological disorders, or poor moral character from serving as special agents. Applicants are screened and interviewed by CID agents at their nearest Provost Marshall's Office (that's military-ese for "police station.")

Army Requirements

To qualify for Army CID, soldiers need a score of at least 107 on the Skilled Technical section of the Armed Services Vocational Aptitude Battery (ASVAB), and at least two years in the military. Applicants with more than 10 years of military service are no longer qualified –- at that point, the Army already invested quite a bit in your previous training, and doesn't want to throw it all away. Soldiers up to the rank of Sergeant (and sometimes Staff Sergeant) are eligible for CID. Would-be agents must also have at least 60 semester hours of post-secondary education, although up to 30 may be waived on a case-by-case basis.

Here's the kicker: Remember when we said you don't necessarily need to be an MP to make the leap to CID? The Army CID Command's website does say applicants must have a "minimum of one year of military police experience or two years of civilian police experience." We'll just point out that CID may choose to waive this requirement for some applicants, and furthermore, they don't say anything about holding the official military police MOS (31B). That means if you were ever assigned outside your MOS to perform MP duties -- which has happened before during MP shortages in wartime –- a case can be made for this requirement.

Marine Corps Requirements

Marines need an ASVAB General Technical score of at least 110. The Corps' MOS Manual differs from Army policy by omitting minimum and maximum time in service and offering a narrow rank window: Sergeants only, with less than two years in grade. Marines from any MOS can apply, and there are no specific educational requirements.


Before attending formal education, prospective Marine CID agents have to undergo a six-month apprenticeship with the local CID office. As far as can be seen on the Army CID Command's website, they don't have a similar prerequisite.

Soldiers and Marines alike are assigned to the 15-week Special Agent Course at Fort Leonard Wood, Missouri, home of the Army's Military Police School. The course covers a range of topics including crime scene investigation and interrogation. In an interview with Colby Hauser of CID Public Affairs, Army Special Agent Ronald Meyer proudly noted that while "other institutions . . . spend maybe two days learning how to process a crime scene, our students here at Fort Leonard Wood spend about two weeks."​

In the same article, Mr. Hauser notes that later in their careers, CID agents may also qualify for advanced education with prestigious organizations like the FBI and Scotland Yard. 

Career Outlook

Unlike many other occupations in the Army and Marine Corps, there are no commissioned officers in the CID. Anyone who wants a salute in CID has to rise up from the ranks to become a warrant officer. Requirements vary between the Army and Marines, but in general, to become a warrant officer in either branch requires at least eight years of total military service and substantial experience and expertise in the MOS. CID warrant officers continue to serve as investigators, but as subject matter experts they also provide guidance and wisdom to enlisted agents and MPs.

Marine Corps special agents, because of their close affiliation with the Navy, may also be eligible for assignment with the Navy Criminal Investigative Service (NCIS.)