I’ve received several emails and a comment or two stating that the Department of Justice asking the Department of Defense to send military lawyers to the border is illegal. Almost all of them cite Posse Comitatus in their claims of illegality. So, is it legal for military lawyers to process non-military criminal immigration cases?
Posse Comitatus states [emphasis added]:
Whoever, except in cases and under circumstances expressly authorized by the Constitution or Act of Congress, willfully uses any part of the Army or the Air Force as a posse comitatus or otherwise to execute the laws shall be fined under this title or imprisoned not more than two years, or both.
In 1986, Congress “expressly authorized” the use of the JAG Corps so long as they are appointed “officers” of the Department of Justice. As such, the JAG officers being assigned to prosecute immigration cases are bring appointed Special Assistant United States Attorneys (SAUSA) by the DoJ which complies with 10 U.S.C. § 806(d) authorizing the use of military lawyers in the prosecution of civilian cases.
In short, it is completely legal for military lawyers to prosecute the crime of illegal entry, a misdemeanor, in civilian court.