What Do Army and Marine Criminal Investigators Do?

Learn About the Salary, Required Skills, & More

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Military police may investigate crimes at bases and installations, but some crimes require a 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.

The Army and the Marines each have their own criminal investigation divisions (CID). Marine Corps special agents, because of their close affiliation with the Navy, also may be eligible for assignment with the Navy Criminal Investigative Service (NCIS.)

Army & Marines Criminal Investigator Duties and Responsibilities

This job generally requires the ability to do the following work:

  • Conduct criminal investigations
  • Collect evidence
  • Conduct interviews and interrogations
  • Process crime scenes
  • Assist with protective services
  • Testify in court
  • Keep records and write reports

CID agents investigate crimes that involve members of the military or otherwise involve the military. Military criminal investigation divisions are similar to detective divisions with civilian police forces, only their jurisdiction involves the military as opposed to a specific civilian municipality. The same sorts of crimes that are investigated by local or state police forces are investigated by military police.

CID agents do sometimes have responsibilities much different from their civilian counterparts. In addition to more common felonies, they also may assist with counterterrorism efforts, investigate war crimes, or provide protective services for key military leaders.

Army and Marines Criminal Investigator Salary

Salaries are based on military pay charts, which take into account both rank and years of service. Criminal investigators must have achieved the rank of sergeant (E-5) and can achieve the rank of chief warrant officer 5 (W-5). The maximum pay rate in any pay grade is for service members with 40 or more years of service. The lowest rate for pay grades E-5 through E-7 is for service members with two years of service or fewer. Service members need at least eight years of service for E-8 pay, at least 10 years of service for E-9 pay, and at least 20 years of service for W-5 pay:

  • E-5 to E-9 Pay Range: $28,721–$98,903 ($13.81–$47.55/hour)
  • W-1 to W-5 Pay Range: $37,397–$122,679 ($17.98–$58.98/hour)

Education, Training, and Certification

A high school diploma is the only requirement to join the Marines, and the Army will accept new recruits with a GED. Acceptance is more likely for anyone with a two-year degree or a four-year degree. Becoming a CID agent specifically requires a minimum of 60 credit hours in college.

  • Training: Whether in the Army or the Marines, aspiring criminal investigators are assigned to a 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. Before attending formal education, prospective Marine agents have to undergo a six-month apprenticeship with a local CID office.
  • Certification: Prospective agents must be eligible for top-secret security clearance and have no criminal record or emotional or psychological disorders. The Army requires a general technical score of at least a 107 on the Armed Services Vocational Aptitude Battery (ASVAB), and the Marines requires a 110.
  • Experience: The Army and Marines require a rank of sergeant to enter the program, and the Army also will not accept soldiers with more than 10 years of military service. The Army also requires one year of MP experience or two years of civilian police experience, though this requirement can be waived.

Army and Marines Criminal Investigator Skills & Competencies

In addition to being in the Army or the Marines and having an interest in and aptitude for criminal investigations, there are several soft skills that will help with success in this career:

  • Attention to detail: The things that might seem like the smallest of clues can have a big impact on criminal investigations. Agents must recognize anything that might be relevant.
  • Analytical thinking: It's not enough to identify clues. Agents must piece together the bits of information they collect to determine what happened.
  • People skills: Agents need to earn the trust of witnesses and crime victims to have the best chance of success with investigations. They also must make connections with suspects to gain insight and information.
  • Strength and stamina: CID agents with the Army or the Marines are required to consistently pass the physical fitness tests for their respective branches of the military, and the job can be physically demanding, especially when dealing with suspects who might pose a physical threat.

Job Outlook

The U.S. Bureau of Labor Statistics does not track CID agents, but job opportunities for all police and detectives are expected to grow about 7% for the decade ending in 2026. This is consistent with the growth rate projected for all jobs during that time period.

Work Environment

Work environments can vary depending on where agents are stationed. Units operate throughout the U.S. and the rest of the world, wherever the U.S. military has a presence. Agents could be in the U.S. collaborating with civilian law enforcement on cases, or they might be in another country or assisting with counterterrorism efforts.

Work Schedule

Schedules for investigators can be unpredictable. Crimes can happen at any time and investigators need to be available to assess crime scenes when evidence is fresh. Working overtime and weekends is common.

How to Get the Job

Interview Skills: Aspiring CID agents need to prepare for a psychological assessment that is part of the interview process.

Physical Fitness: Prepare physically by making sure you can meet the fitness standards.

Resume: Use your resume to highlight the skills you learned as an MP or as a civilian police officer.

Comparing Similar Jobs

People interested in criminal investigator careers in the Army or Marines also might consider one of the following career paths, listed with median annual salaries: