Who is primarily responsible for investigating fraud claims against military health insurance programs?

The Defense Criminal Investigative Service (DCIS) is the correct choice because it is specifically tasked with investigating fraud against military health insurance programs. As a component of the Department of Defense, DCIS's primary mission includes the prevention, detection, and investigation of fraud, waste, and abuse in defense-related health care programs, including TRICARE, which is the health care program serving military personnel and their families.

DCIS has the authority to investigate criminal activities that directly impact the Department of Defense, making it uniquely positioned to address issues arising from fraud claims in military health insurance.

In contrast, while the Federal Bureau of Investigation (FBI) is involved in a wide range of criminal investigations, its role is more general and does not focus specifically on military health care fraud. The Department of Health and Human Services (HHS) primarily oversees health care policies and programs, but it does not directly handle criminal investigations against military health insurance. Lastly, the Office of the Inspector General (OIG) is involved in oversight and audits, but in the context of military health fraud, the DCIS is specifically designated for investigative responsibilities.