Judge Advocate General's Corps (United States)

Judge Advocate General's Corps, also known as JAG or JAG Corps, refers to the legal branch or specialty of the U.S. Air Force, Army, Coast Guard, and Navy. Officers serving in the JAG Corps are typically called Judge Advocates. The Marine Corps and Coast Guard do not maintain separate JAG Corps per se and judge advocates in those services maintain their line-officer status. In the Air Force and Navy, JAG officers only serve in legal positions. Judge Advocates in the Army retain eligibility for command, and may be assigned to non-legal positions with permission of the Judge Advocate General, but this is only rarely done; the majority serve in legal positions and their careers are therefore similar to those of the Navy and Air Force.

Judge Advocates serve primarily as legal advisors to the command to which they are assigned. In this function, they can also serve as the personal legal advisor to their commander. Their advice may cover a wide range of issues dealing with administrative law, government contracting, civilian and military personnel law, law of war and international relations, environmental law, etc. They also serve as prosecutors for the military when conducting courts-martial. They are charged with both the defense and prosecution of military law as provided in the Uniform Code of Military Justice. Highly experienced officers of the JAG Corps often serve as military judges in courts-martial and courts of inquiry.

The services also have enlisted soldiers with specific paralegal training that provide support to Judge Advocates, although accession and scope of duty is also branch-specific. For example, the U.S. Army permits new recruits to become Judge Advocate enlisted, while the U.S. Navy does not. In addition to acting as paralegals to military attorneys, JAG enlisted often provide limited paralegal services such as drafting commonly used legal documents for servicemembers and their families, providing guidance to unit commands regarding administrative and disciplinary procedure, and acting as notaries.

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