Small Wars Journal

The Posse Comitatus Act and the American Military: An Old Law Under a New Light

Wed, 01/25/2023 - 9:19am

The Posse Comitatus Act and the American Military: An Old Law Under a New Light
By Travis L. Eddleman


Over the last several years, the Posse Comitatus Act (PCA), a piece of federal legislation dating back to 1878, has made a comeback to the forefront of American political commentary, legal review, and military consideration.  In 1960, Furman referred to the PCA as nothing more than “a maze to be threaded by each Commander at each request for troops” (p. 97).  However, recent usage of National Guard troops in Portland, OR, and Washington, D.C., along with numerous deployments of Army personnel (under both Title 10 and Title 32 authority) to the Southwest Border have reignited public debate surrounding the PCA, the  Insurrection Act, and the state of the nation with the perception of an increasingly pervasive military presence in the realm of civilian law enforcement (Cohen & Stevens, 2021; Ghiotto, 2020). Many of these instances arise through the exercising of the Insurrection Act, a series of laws passed in the late 18th and early 19th centuries that now act as an exception to the provisions of the Posse Comitatus Act (Goitein & Nunn, 2022). 

History of the PCA

The PCA has changed since its inception in 1878.  The Act was originally worded as follows:

It shall not be lawful to employ any part of the Army of the United States, as a posse comitatus, or otherwise, for the purpose of executing the laws as, except in such cases and under such circumstances as such employment of said force may be expressly authorized by the Constitution or by act of Congress. (Posse Comitatus Act, 1878)

However, in 1956 the act was repealed and reenacted under Title 18 U.S.C. 1385 (Furman, 1960).  The PCA now reads differently to incorporate the Air Force and indicate the criminal penalties of violating the Act.

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. (18 U.S.C. 1385)

The two incidents that most impacted the congressional decision to pass the PCA largely centered on disorder in the state of Kansas and the use of the military for post-Civil War election supervision (Furman, 1960). Despite the intent of the act to limit the use of federal troops on U.S. soil, the Army acted, according to Furman (1960), approximately seventy times in situations ranging from labor disputes to natural disasters and elections from inception of the PCA in 1775 up until 1878. President Hayes, who signed the bill, considered it to be more focused on the U.S. Marshals service and sent federal troops to enforce judicial proceedings in New Mexico less than 120 days after signing the bill into law (Harman-Heath, 2021). Historically speaking, the U.S. Marshals Service had exercised the same authority as local Sheriffs to enlist the assistance of the U.S. Military to locate and/or apprehend a fugitive or execute the enforcement process (Barr, 1989; Furman, 1960).

President Cleveland sent federal troops to handle an ongoing railroad strike in 1879, and President McKinley sent approximately 500 troops to Idaho in 1899 (Harman-Heath, 2021). In more modern times, the PCA has been called into question following the arrest of a Nazi Propagandist by the U.S. Military following World War II and the incident at Wounded Knee in 1971 during which military personnel advised civilian law enforcement (Harman-Heath, 2021). During World Warr II, the Army helped circumvent the PCA by employing Auxiliary Military Police who, while not in the military service themselves, were outfitted and armed with Army equipment (Furman, 1960). Even in the early 1950s, conflict arose between the U.S. Army and the Attorney General’s Office concerning the deployment of troops to guard the southern border with Mexico.  Ultimately, the Army believed no authority existed to take such actions while the Attorney General’s office ruled “the President’s broad Constitutional power were sufficient to override the Posse Comitatus Act” (Furman, 1960, p. 126).  In more modern instances, Govern (2018) made numerous references to situations where the President activated troops under exceptions to the PCA, including President Wilson in 1919, President Hoover in 1932, President Truman in 1946, President Eisenhower in 1957, President Kennedy in 1962, President Nixon in 1972, President George H.W. Bush in 1992, and President George W. Bush in 2005.

The PCA makes no direct reference to the National Guard component but “it is generally understood that when the National Guard is under federal control, the Act applies (Samek, 2007, p. 378-379). In very recent history, President Trump called in National Guard Forces from 11 states and the District of Columbia in a Title 32 (non-federalized) status to address protests against police brutality in the nation’s capital (Rosenberg & Dayton, 2022). These 11 states provided their Troops by request of the President and Secretary of Defense, not the mayor of Washington D.C., an act which was supported by then Attorney General William Barr via a letter to the D.C. mayor (Rosenberg & Dayton, 2022). Since that time, legislators have acted to realign the D.C. National Guard under the control of the mayor and not the President (Norton joins DEM colleagues in seeking mayoral control over D.C. National Guard, 2022).   

PCA and the Southwest Border

Although border security is not among one of the many missions assigned to the U.S. Military, the military is often called upon to assist and support other federal agencies, to include law enforcement and immigration authorities (Mason, 2010). There has existed for several years a growing argument that the border situation poses a “national threat” which would allow for some latitude to deploy Troops to the Southern Border (Mason, 2010). The Congressional Research Service has documented various instances in which Presidents have utilized the national guard on the southwest border, to include President George W. Bush’s activation of 6,000 national guard troops in support of Border Patrol and “Operation Jump Start” which included more than 30,000 national guard troops deployed along the border (Mason, 2010). President Obama, in 2010, deployed over one thousand national guard troops to the border, specifically stating they would “help with intelligence work, drug and human trafficking interdiction, and relieving border guards on security tasks so they can do more law enforcement” (Daniel, 2010). 

Under 18 USC 1385, the military holds legislative authority to act in a supporting capacity to law enforcement agencies conducting specific activities such as counterdrug, counternarcotics, and specific border-related issues. The PCA limits the executive branch to deploy the military only into situations or circumstances specifically authorized by the congress.  Congress has several standing exceptions, according to Mason (2010), contained within Chapter 18 of Title 10 of the U.S. Code, specifically entitled “Military Support for Civilian Law Enforcement Agencies.”  These standing exceptions to the PCA allow department of defense entities “to share information (§ 371); loan equipment and facilities (§ 372); provide expert advice and training (§ 373); and maintain and operate equipment (§ 374)” (Mason, 2020 p. 4).

The President can bring the National Guard under federal authority utilizing Title 10 USC 12301-12304, under which the National Guard is subject to the provisions of the PCA.  However, the President may also activate the National Guard into a Title 10 status under 10 U.S.C. 331-333 and 12406 to “execute the laws of the United States.”  In doing this, the military would no longer be subject to the parameters of the PCA and could enforce civilian law. 

Many DOD officials, when questioned by Government Accountability Office (GAO) researchers expressed significant concerns with the challenges of implementing federal troops under Title 10 of the U.S. Code to support law enforcement on the Southwest Border (Lepore, 2012). In 1960, Furman opined

the statute is limited to deliberate use of armed force for the primary purpose of executing civilian law enforcement channels, and that those situations where an act performed primarily for the purpose of insuring (sp) the accomplishment of the mission of the armed forces incidentally enhances the enforcement of civilian law do not violate the statue (p. 128).

However, current legal researchers have raised growing concerns over the continuously expanding power flexed by the executive branch based upon the authority garnered from the Insurrection Act of 1807 (Cohen & Stevens, 2021). Ghiotto (2020) argued “there has been a gradual encroachment by the military into civilian law enforcement matters” (p. 360) resulting in “constitutional dysfunction regarding the use of military power” (p. 418). Congruently, Cohen and Stevens (2021) believed the extensive power wielded by the executive branch regarding deployment of federal troops within our own borders poses a significant threat to the basic civil liberties enjoyed by U.S. citizens (they fear the slippery slope of the military being turned inward on our own citizens). Additionally, Rosenberg and Dayton (2022) view the recent interpretation of the President’s authority in utilizing the National Guard on U.S. soil as a threat to “state sovereignty [that] raises serious constitutional concerns” (para. 14).


In February of 2013, the Department of Defense issued DOD Instruction 3025.21 which required DOD entities to develop necessary procedures required to commit DOD resources in the event of a civil disturbance.  Since that time, the government has held national level exercises to improve hurricane preparedness at the national level.  Govern (2018) has suggested the time has come to consider similar exercises and national level oversight for integration of state, local, and other federal assets along with the military to address the situation on the southern border. The U.S. House of Representatives has recently acted through a proposed bill that would require interstate deployment of the National Guard in a Title 32 status to have approval of both state governors and an additional measure to place the D.C. National Guard under the control of the mayor, not the President (Rosenberg & Dayton, 2022). Furthermore, legal and constitutional scholars have called for a review of the Insurrection Act to correct “vague and overbroad” language that leaves the president exercising “limitless discretion” to utilize Soldiers, Sailors, Airmen, and Marines in a domestic situation that is largely interpreted as the politicization of the military (para. 5).     

The politico-military environment has shifted significantly since Furman flippantly dismissed the PCA as a mere “maze to be threaded by each Commander at each request for troops” (p. 97). In a world that has changed drastically, the protests of 2020, the January 6th riots at the U.S. Capitol, and an ongoing military presence at the United States’ southwest border, have brought the U.S. Military, both active and reserve components, to the forefront of political warfare.  With growing fear of domestic military operations and the threatened politicization of the military, the Posse Comitatus Act and the Insurrection Act are now far more than simple matters of a ground level commanders’ interpretation.  Pending legislation may likely close the existent loopholes within the Insurrection Act, strengthen the Posse Comitatus Act, and create additional hurdles for military commanders and political leaders who view the military as the appropriate tool to address civil unrest and border insecurity.




Cohen, M., & Stevens, J. (2021). Nation joins in tears: implications of the domestic deployment of federal troops in Portland, Oregon. North Carolina Civil Rights Law Review, 1(1),       120-163.

Furman, H. H. (1960). Restrictions upon use of the army imposed by the posse comitatus act. Military Law Review, 7, 85-130.

Committee on Homeland Security & Lepore, B. [Report], Border Security: Observations on costs, benefits, and challenges of a Department of Defense role I helping to secure the   southwest land border; Testimony before the Subcommittee on Border and Maritime  Security, Committee on Homeland Security, House of Representatives, 1-16 (2012).   Washington, D.C.; U.S. Govt. Accountability Office.

Ghiotto, A. J. (2020). Defending the military: the posse comitatus act's exclusionary rule. Harvard National Security Journal, 11(3), 359-419.

Goitein, E. & Nunn, J. (2022 September 20). How to fix the Insurrection Act. Brennan Center for  Justice. Retrieved January 15, 2023, from  work/analysis-opinion/how-fix-insurrection-act.

Govern, K. (2018, October 19). National Guard and active duty lend a hand to civil authorities   on the border. Jurist. Retrieved January 15, 2023, from borders/

Harman-Heath, S. A. (2020-2021). The quasi-army law enforcement, value judgments, &

            the Posse Comitatus Act. California Law Review Online, 11, 367-386.

Reiteration of the use of soldiers to enforce elections proceedings in the post-civil war  south (Harman-Heath, 2021).

Mason, R. (2010, June 16). Securing America’s borders: The role of the military (CRS Report  No. R41286).

Norton joins DEM colleagues in seeking mayoral control over D.C. National Guard. The Washington Informer. (2022, December 1). Retrieved January 20, 2023, from  control-over-d-c-national-guard/

Samek, J. (2007). The federal response to Hurricane Katrina: A case for repeal of the Posse  Comitatus Act or a case for learning the law? University of Miami Law Review, 61(2). p.    441-465.

Zimmerman, A. (2020). Federal troops in the Portland, Oregon protests. Voices in Bioethics, 6, p. 1-5.



About the Author(s)

Travis L. Eddleman is a Battalion Commander in the Arkansas Army National Guard and a Deputy United States Marshal assigned to the Western District of Missouri.  He holds a D.Sc. in Civil Security Leadership, Management, and Policy (New Jersey City University, 2021). His interests include criminal investigative studies, leadership studies, and issues impacting the traditional, drilling guardsman.