Fact check: Which branches of the US military are explicitly covered by the Posse Comitatus Act?

1. Summary of the results

The Posse Comitatus Act explicitly covers the Army and Air Force ^{[1] [2]}. The Air Force was added to the Act in 1956, as it was created after the original 1878 law ^[3]. While not directly covered by the Act itself, the Navy and Marine Corps are subject to the same restrictions through separate Department of Defense regulations ^[2].

2. Missing context/alternative viewpoints

Several important contextual elements are missing from the original question:

• The Coast Guard is explicitly exempt from the Act's restrictions ^[1], as it serves as a police force during peacetime ^[2]
• The National Guard has a unique dual status:
• When under state control, they are not covered by the Act
• When federalized, the Act's restrictions apply ^[4]

3. Potential misinformation/bias in the original statement

The question itself could lead to misunderstanding by focusing only on "explicit" coverage, when the practical application of the law is more complex:

• While only the Army and Air Force are explicitly mentioned in the Act, all military branches are effectively restricted from domestic law enforcement through various legal mechanisms ^[3]
• The law has been subject to various amendments and interpretations over time ^[4]
• The distinction between explicit coverage in the Act itself versus coverage through other statutes and regulations is largely administrative rather than practical ^[2]

This complexity in legal coverage reflects the evolving nature of both military organization and domestic security needs since the Act's original passage in 1878.