Skirting the constraints of Posse Comitatus


The image of 100,000 National Guard troops patrolling residential streets to detain and deport undocumented immigrants is, at best, unsettling. The Posse Comitatus Act (PCA) limits the executive’s authority to order such a mobilization domestically to perform law enforcement functions.  Couching immigration raids as necessary to protect our national security could permit the Trump administration to usurp the limitations of the PCA. If the administration attempts to mobilize armed soldiers in cities across the country, not only would it create bad optics, but also implicate very practical concerns for those soldiers and communities.

In large part, National Guard soldiers are residents of the state in which they serve. If mobilized to perform the functions of immigration officers, they could be detaining, imprisoning and deporting family members and friends from their own community. The same community that soldier will return to after their mobilization has ended.

{mosads}The threat of such a large domestic mobilization came to the political forefront after the release of a draft DHS memorandum requesting National Guard troops to perform immigration operations which re-ignited the debate over the president’s authority to federalize a militia vis-à-vis the PCA. The express directive for National Guard troops was removed from the final version of the memorandum but still leaves open the possibility of National Guard involvement.

The PCA authorizes the president to mobilize the National Guard in a particular state with the governor’s consent. In order for the president to not run afoul of the PCA, the draft memorandum directed the engagement of National Guard troops with the agreement of state governors in order “to perform the functions of an immigration officer in relation to the investigation, apprehension, and detention of aliens in the United States.” The final DHS memorandum authorizes CBP and ICE “to accept State services and take other actions as appropriate to carry out immigration enforcement. . . .” which suggests National Guard involvement.

At its most basic level, the PCA proscribes the role of the military in executing civil laws. The PCA was passed as a direct result of the Army’s involvement in Reconstruction in the South and President Grant’s domestic mobilization of military forces during that time. Determined to remove military forces from their streets, Southern Democrats successfully passed an amendment to the Army appropriations bill that prohibited the president from mobilizing military forces domestically. The amendment became known as the PCA and was signed into law in 1878.

The PCA contains several exceptions and the most widely used is the exception for National Guard forces operating under state authority. Federalizing the National Guard under these exceptions is not an unprecedented action. In 1957, President Dwight Eisenhower federalized the Arkansas National Guard to protect African-American students integrating into a previously all-white high school.  In 1986, the executive branch issued a directive declaring the “war on drugs” a national security matter and ordered the military to provide tactical assistance to local law enforcement to aid the domestic policing of drug laws. By executive order and the Insurrection exception, George H. W. Bush deployed active duty troops to the city of Los Angeles in 1992 to quell the violence in response to the Rodney King verdict.

Though PCA exceptions shape the president’s authority over the National Guard and U.S. military on domestic soil, the limitations of the PCA may not be enough to prevent the militarization of immigration enforcement under a “national security” narrative. President George W. Bush nearly bypassed the PCA in such a manner after 9/11 when a Justice Department memorandum suggested that the President could unilaterally mobilize U.S. troops domestically to arrest a group suspected of plotting with al Qaeda because the operation was aimed at protecting national security rather than performing civil police enforcement. Though the president ultimately decided against sending in U.S. troops, had he done so, it would have been the first time active-duty military were deployed on U.S. soil without specific statutory authority since the Civil War.

The Trump administration could utilize a similar tactic, particularly in light of the directive set forth in the final DHS memorandum prioritizing enforcement against individuals who “in the judgment of an immigration officer, otherwise pose a risk to public safety or national security.” While DHS Secretary Kelly stated the U.S. would not use military forces for this function and White House press secretary Sean Spicer clarifying the president’s statement classifying illegal immigrant deportations as “a military operation” as an adjective, given the campaign promise to erect a deportation force we may soon see soldiers on our streets.

Timothy M. MacArthur is a Clinical Professor and Director of the Mason Veterans and Servicemembers Legal Clinic at the Antonin Scalia Law School at George Mason University. Leigh Winstead is the Managing Attorney for the Mason Veterans and Servicemembers Legal Clinic where she oversees all civil litigation matters in the clinic and manages the daily operations of the clinic.

The views expressed by this author are their own and are not the views of The Hill.


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