he Posse Comitatus Act forbids the willful use of “any part of the Army or the Air Force as a posse comitatus or otherwise to execute the laws.” It has been applied as well to the Navy and Marine Corps.
A military serviceman stands guard on the US side of the US-Mexico border fence as seen from Playas de Tijuana, Mexico, on November 16, 2018., Pedro Pardo/AFP/Getty Images
Donald Trump’s decision to send thousands of troops to the US-Mexican border to intercept migrants who intend to apply for asylum is not just a bald-faced political stunt — it is also illegal.
Passed in 1878 to end the use of federal troops in overseeing elections in the post–Civil War South, the Posse Comitatus Act forbids the use of the military to enforce domestic US laws, including immigration laws. For this reason, Trump’s decision to deploy the military to the border to enforce US immigration law against thousands of desperate migrants from Central America — who have undertaken the perilous journey over 1,000 miles through Mexico to the US border in order to apply for asylum — is an unlawful order.
Kathleen Gilberd, executive director of the National Lawyers Guild’s Military Law Task Force, told Truthout, “The deployment of US troops to the Southern border is an illegitimate political ploy and a serious misuse of the military. This action casts shame on a government that treats refugees seeking asylum as enemies.”
The illegality of Trump’s order to the military opens the door to the possibility that service members will resist it: Under the Uniform Code of Military Justice, Nuremberg Principles and Army Field Manuals, service members have a duty to obey lawful orders and a duty to disobey unlawful orders.