Posse comitatus
Posse comitatus is a legal principle that emphasizes the use of civilian law enforcement over military involvement in maintaining public order. Originating from ancient Rome and evolving through English legal traditions, the term refers to the collective efforts of able-bodied citizens summoned by a sheriff to assist in quelling disturbances. The Posse Comitatus Act of 1878 explicitly prohibits the use of military forces in enforcing civilian laws, a response to concerns during the Reconstruction era about federal troops interfering in local matters. While the act primarily applies to the Army, other branches, like the Navy and Marines, also adhere to its principles as a matter of policy.
Although the act has been amended over time, particularly in 1981 to allow some military support for civilian law enforcement, the core tenet remains that military personnel cannot directly engage in civilian enforcement actions. Historically, posses played a role in local law enforcement, but their formation sometimes led to instances of vigilantism and abuses of power. In contemporary culture, the term has been appropriated by various groups, including an antitax militia that emerged in the 1960s, which interprets constitutional rights in a specific manner. As such, the concept of posse comitatus continues to evoke discussions about the balance between civil authority and military power in American society.
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Posse comitatus
SIGNIFICANCE: The posse comitatus concept requires able-bodied adults to assist civilian law-enforcement officials when requested to do so; under federal law, the principle specifically exempts military involvement.
Posse comitatus means “the entire power of the county” from which the sheriff can draw able-bodied adults to help quell civil disturbances. The name derives from ancient Roman times, when traveling government officials were accompanied by their retainers, a practice known as comitatus. The posse comitatus can be traced to the jurata ad arma of the feudal kings of England, whereby all freemen over fifteen years of age were required to own weapons and to be available for the king’s defense. Eventually this civilian force became known as the posse comitatus, or simply posse.
The issue of who should be allowed to be in a posse has long been scrutinized. Except in extreme circumstances, the posse comitatus is composed of civilians under civilian authority. In English tradition, this separation of civil from military law enforcement can be traced to King John’s signing of the Magna Carta in 1215. In the United States, the Posse Comitatus Act of 1878 stated that military personnel were not to be included in posses.
Passed in response to post–Civil War complaints of southerners that federal troops were being used to enforce civilian laws during Reconstruction, the Posse Comitatus Act instituted the separation between civilian forces under a civil control from martial forces under military control and proscribed the use of the military to quell civilian disturbances. Although the Navy and Marines are not specifically governed by the act, those branches of the military adhere to the act’s prohibitions as a matter of policy. The Air Force was included in later amendments to the act.
The 1981 amendments to the act eroded its stand against the involvement of the military in law enforcement. These amendments, enacted in response to the increased power of drug smugglers, whose organizations and equipment rivaled those of some countries’ military forces, delineated the military’s role in civil law enforcement. In theory, the separation between civil and military law enforcement is still intact, but the 1981 amendments allow the military to supply civilian law-enforcement authorities with equipment, information, and facilities. They do not allow direct involvement of military personnel in civilian law enforcement.
The familiar posse of the American frontier was used to apprehend felons. Members of the community were deputized by sheriffs and federal marshals to chase rustlers and others who breached the peace. Sometimes the formation of posses led to abuses and vigilantism under the color of law, including abuses by groups such as the Ku Klux Klan. In modern times, the name “Posse Comitatus” was taken by an antitax vigilante group. This Posse Comitatus, a militant, armed survivalist group founded in the 1960s, believes in a reading of the U.S. Constitution that excludes all amendments beyond the first ten.
Bibliography
Abrahams, Ray. Vigilant Citizens: Vigilantism and the State. Cambridge, England: Polity Press, 1998.
Buttaro, Andrew. "The Posse Comitatus Act of 1878 and the End of Reconstruction." St. Mary's Law Journal 47.1 (2015): 135–186. PDF file.
Kopel, David. "The Posse Comitatus and the Office of Sheriff: Armed Citizens Summoned to the Aid of Law Enforcement." Journal of Criminal Law & Criminology 104.4 (2015): 761–850. PDF file.
Neely, Richard. Take Back Your Neighborhood: A Case for Modern-Day “Vigilantism.” New York: Penguin USA, 1990.
Nevitt, Mark. "Domestic Military Operations--The Role of the National Guard, Posse Comitatus Act and More." Just Security, 21 Oct. 2020, www.justsecurity.org/72988/good-governance-paper-no-6-part-two-domestic-military-operations-the-role-of-the-national-guard-posse-comitatus-act-and-more/. Accessed 9 July 2024.
Nunn, Joseph. "The Insurrection Act Explained." Brennan Center for Justice, 21 Apr. 2022, www.brennancenter.org/our-work/research-reports/insurrection-act-explained?shem=ssc. Accessed 9 July 2024.
Sharum, Jerald A. "The Politics of Fear and Outsourcing Emergency Powers: The Death and Rebirth of the Posse Comitatus Act." Lincoln Law Review 37 (2009): 111–48. PDF file.