Ivan Hoffman, B.A., J.D.

           One of the legal guardians against control of the government by the military (also known as martial law) is the little-known-until-now “posse comitatus” act (“The Act”).  The Act was designed to prevent use of the military to enforce laws against non-military persons.   


         The origins of the law (literally meaning “power of the county”) go back into English common law and refer to the ability of a sheriff to summon all the able-bodied men over 15 to enforce the law or preserve the peace against those who would disobey it. 

         The Act, which became law in 1878, is set forth in United States Code section 18 USC 1385 and it reads:

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. 

         Whether the President or other government officer has the power to call up the military in a given situation depends, like all law, on the circumstances.

         During the George H. W. Bush and Obama administrations, the President had the Department of Defense deploy the National Guard on United States soil to assist Border Patrol but they did not perform law enforcement duties and instead performed a variety of administrative and logistical activities.   However, it could be argued that the states, which control the use of the National Guard in such instances, could give those troops law enforcement capabilities. 

         For purposes of this article, I will use the circumstances of the “caravan” wending its way through Central American ostensibly on the way to the United States to seek asylum or other entry into the country.

The Details 

         Initially, the President has to make a declaration that the situation has to have reached a point of crises bordering on lawlessness.  Thus the threshold determination has presumably to be based on findings of fact.   

         The Act does not apply to use of the National Guard because they are not “the Army or the Air Force” and because such troops are technically under the control of the governor of the state in which they are deployed.  The Act applies to the use of military to enforce federal law.  The Act would apply, however, if the National Guard were mobilized to enforce federal law. 

         Thus, under section 502 (f) of 32 U.S.C., which applies solely to the use of National Guard, not regular army troops, these troops can be used to provide “homeland defense activities” which are defined as activities: 

undertaken for the military protection of the territory or domestic population of the United States, or of infrastructure or other assets of the United States determined by the Secretary of Defense as being critical to national security, from a threat or aggression against the United States. 

         So presumably any such findings have to fall within the above express provisions including that there must be a determination by the Secretary of Defense that there is a need for “military protection of the territory or domestic population of the United States”… from a “threat or aggression against the United States.”   Such a finding would appear, under the circumstances, to not be warranted from what we know about the “caravan” which appears to be civilians seeking asylum. 

         Should a governor of a state claim that such troops are needed for drug interdiction purposes, the statute allows for the use of those troops for that purpose.   

         But what if, as in the example in this article, the troops being used are regular army troops? 

         In such event, as indicated above, the Act requires that the actions of the President fall within the express authorization “of the Constitution or Act of Congress….” 

         The Constitution, in Article I, Section 8 provides in part for the power of the Legislature: 

15: To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;

16: To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress;

        In furtherance of such powers, the Legislature enacted The Act. 

        Furthermore, Title 10, section 252 of the United States Code, provides that the President can use the armed forces of the United States in the event of “unlawful obstructions, combinations, or assemblages or rebellion against the authority of the United States….” if enforcement of the laws is “impracticable…by the ordinary course of judicial proceedings….” 

        Assuming that the foregoing section does not apply under the facts, there does not appear to be any express authority to use federal armed forces to protect the border or to enforce immigration laws.  However the same Title 10 provides that the armed forces can be used by the Secretary of Defense to provide non-law enforcement support to state and federal law enforcement agencies.  Section 275 of that Title provides: 

The Secretary of Defense shall prescribe such regulations as may be necessary to ensure that any activity (including the provision of any equipment or facility or the assignment or detail of any personnel) under this chapter does not include or permit direct participation by a member of the Army, Navy, Air Force, or Marine Corps in a search, seizure, arrest, or other similar activity unless participation in such activity by such member is otherwise authorized by law. 

         The last phrase is key and requires a determination if such activities are “otherwise authorized by law.”  Congress has authorized the Department of Defense to use the military to enforce drug smuggling laws but there would have to be a determination that there was such international drug smuggling or other international crime going on in the “caravan.”  And even if such a determination were made, the activities of the military still do not allow for their use to enforce laws but only for non-law enforcement support.

         So obviously the dividing line between permissible and impermissible use of the military is a legally fuzzy one.  One of the key cases in this area is the 2014 Ninth Circuit decision in United States vs. Dreyer.  In that instance, the Naval Criminal Investigative Service (“NCIS”) was investigating criminal activity by anyone in the state of Washington, whether those parties were connected with the military or not.  In the process, the NCIS discovered evidence of violation of child pornography laws by the defendant, a civilian, and turned the case over to the state for prosecution.  The Court outlined the tests used to determine whether the activities of the military are covered by The Act.  It stated: 

We have “set forth three tests for determining whether military involvement in civilian law enforcement constitutes permissible indirect assistance: ‘[1] The involvement must not constitute the exercise of regulatory, proscriptive, or compulsory military power, [2] must not amount to direct active involvement in the execution of the laws, and [3] must not pervade the activities of civilian authorities.’ “ Hitchcock, 286 F.3d at 1069 (quoting Khan, 35 F.3d at 431).10 “If any one of these tests is met, the assistance is not indirect.” Khan, 35 F.3d at 431.

         The Court of Appeals held that such actions as were used by the NCIS violated The Act. 


The Dreyer Court stated: 

The PCA [Posse Comitatus Act] was originally enacted on the understandings that “[t]he great beauty of our system of government is that it is to be governed by the people,” and that if we use the “military power ․ to discharge those duties that belong to civil officers and to the citizens,” we “have given up the character of [our] Government; it is no longer a government for liberty; it is no longer a government founded in the consent of the people; it has become a government of force.” 7 Cong. Rec. 4247 (1878) (remarks of Sen. Benjamin Hill). 

Also read “The Enabling Act.”

Copyright © 2018 Ivan Hoffman.  All Rights Reserved. 

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Ivan Hoffman has been practicing intellectual property law for over 45 years and has written extensively about that topic. (  Additionally, Ivan Hoffman has written numerous books about philosophy including “The Tao of Love” and “The Tao of Money.” 


This article is not legal advice and is not intended as legal advice.  This article is intended to provide only general, non-specific legal information.  This article is not intended to cover all the issues related to the topic discussed.  You should not rely on this article in any manner whatsoever and you should not draw any conclusions of any sort from this article.  The specific facts that apply to your matter may make the outcome different than would be anticipated by you.  This article is based on United States laws but the laws of other countries may be different.  You should consult with an attorney familiar with the issues and the laws of your country.  This article does not create any attorney client relationship and is not a solicitation.      



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