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Posse Comitatus Act: What Does It Mean to Local Law Enforcement?

NCJ Number
Police Chief Volume: 71 Issue: 7 Dated: July 2004 Pages: 46-48
John W. Probst
Date Published
July 2004
3 pages
This article reviews the origin and definitions of the Posse Comitatus Act, which prohibits the use of Federal troops to enforce civilian law, as well as its impact on recent events and its present-day standing.
The original Posse Comitatus Act (PCA) was a rider to an appropriations bill approved on June 18, 1878. It prohibits the use of Federal troops to enforce civilian law "except in such cases and under such circumstances as such employment of said force may be authorized by the Constitution or by act of Congress." This qualification allowed the use of Federal forces against the 1919 rioters in Chicago, the so-called Bonus Marchers in Washington, DC in 1932, and the railroad workers who went on strike during the administration of President Truman, who temporarily nationalized the railroads under the Army Corps of Engineers. More recent implementations of the exceptions to the PCA were the 1973 standoff between Federal troops and the American Indian Movement at Wounded Knee, SD; the 1992 street riots in Los Angeles after the Rodney King verdict; the 1993 standoff with the Branch Davidians at Waco, TX; the bombing of the Federal building in Oklahoma City; and the 2001 suicide attacks on the World Trade Center and the Pentagon. These events involved the deployment of Federal troops in domestic incidents, and observers critiqued these events as involving too much or too little military involvement. Since the September 11th attacks by foreign terrorists, there is renewed interest in examining the various roles of the military in preventing and responding to various types of domestic-security incidents. The debate surrounding the rationale for and provisions of the PCA has intensified under the significant domestic threat of foreign terrorists. 8 notes