Under Article IV, Section 4 of the U.S. Constitution, the federal government is ordered to protect the states from invasion, and upon request from state governors or legislature, protect them from “domestic violence.” Article 1, Section 8 requires Congress to call forth troops to “execute the Laws of the Union, suppress Insurrections and repel Invasions.”

Subsequent federal laws have further described when federal troops can be mobilized in the states. The Stafford Act gives the president broad powers to use federal resources during a disaster, however the Posse Comitatus Act prohibits the Army or Air Force from engaging in law enforcement in most situations. The Insurrection Act allows the president to mobilize, in response to a state request, federal troops in order to suppress “insurrection, domestic violence, unlawful combination, or conspiracy,” in situations where state law enforcement is compromised. In 2006, this law was re-named the “Enforcement of the Laws to Restore Public Order” act and was amended to give the president to order troops to function as law enforcement without a state request during time of emergency.

Disturbingly, outside of this legislative framework, the Congressional Research Service reports that the Department of Defense has adopted a policy to authorize “prompt and vigorous Federal action, including use of military forces, to prevent loss of life or wanton destruction of property and to restore governmental functioning and public order,” when local authorities are overwhelmed.

I discovered a partial list of times the Constitution’s domestic violence clause has been invoked as an appendix to the Kerner Commission report, which also appears in Deputy Secretary of Defense Cyrus R. Vance’s report. I have edited the original descriptions slightly for length and added several post-1968 events. (The original is here.)

STATE REQUESTS FOR FEDERAL ASSISTANCE IN SUPPRESSING DOMESTIC VIOLENCE
A Chronological List of Major Requests

1838 – Buckshot War. President Van Buren requests request for federal assistance when violence results from bitter political contest.

1842 – Dorr Rebellion. President Tyler refuses to dispatch troops to protect Rhode Island Governor King from insurgent Dorr.

1856 – San Francisco Vigilance Committee. California requested assistance to stop the Committee from usurping the authority of the State. President Pierce took no action on the advice of his attorney general.

1873-1875 – New Orleans unrest. President Grant dispatches two regiments of troops to New Orleans during reconstruction to protect the Republican government from a Democratic white militia, and in 1875 to protect the government from a white coup d’état.

1876 – South Carolina riots. Violence between the Ku Klux Klan and black state militia prompts the president to station troops at 70 places in the state to oversee the election.

1877 – Railroad Strike riots. President Hayes issues proclamation to West Virginia, Maryland, Pennsylvania, and Illinois to restore order. Ohio receives federal arms. Michigan, Wisconsin and California also made requests for help.

1892-1899 – Idaho’s Coeur D’Alene mining disturbances. Presidents Harrison, Cleveland and McKinley provide Idaho Governors assistance to quell labor violence.

1894 – Coxey’s Army of unemployed. President Cleveland instructed the army to assist Montana in quelling violence in Coxeyite contingent in Montana.

1903 – Colorado mining strike disturbance. President Theodore Roosevelt denies request to Colorado Governor to provide assistance during mining strike.

1907 – Nevada mining disturbance. President Roosevelt orders troops to assist state authorities to maintain order.

1914 – Colorado coal strike. President Wilson sent troops to stop rioting after negotiations for peaceful resolutions fails.

1919 – Race riots in Washington, D.C. and Omaha; Gary steel strike. Secretary of War instructs troops to respond to state requests.

1921 – West Virginia coal mine warfare. President Harding responds to a request by the West Virginia governor and Federal troops disarm striking miners.

1932 – The Bonus Army. Needy veterans camping in Washington are dispatched by federal troops. (No state request)

1943 – Detroit race riots. Federal troops dispatched to Detroit to keep the peace after race riot.

1957 – President Eisenhower sends federal troops to Little Rock to keep the peace during the integration of Little Rock High School. (No state request)

1963 – President Kennedy orders federal troops to Oxford, Mississippi to quell riots caused by the integration of University of Mississippi. (No state request)

1967 – Detroit riots. Federal troops dispatched to Detroit in July 1967 at request of governor to stop rebellion.
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1968 – Washington, D.C. Martin Luther King, Jr. Rebellion – The federal government mobilizes troops to protect federal buildings and keep order.

1971 – May Day Protests – President Nixon mobilizes thousands of federal troops to keep the government open when anti-war activists tried to close the government through a mass protest.

1989 – Hurricane Hugo. The president sends federal troops to St. Croix, Virgin Islands to control violence and looting under the powers of the Insurrection Act.

1992 – Rodney King uprising. California Governor Pete Wilson requests and receives federal assistance to quell violence erupting after the acquittal of police officers accused of beating Rodney King.

2005 – Hurricane Katrina in New Orleans. Louisiana Governor Kathleen Blanco requests and receives 40,000 federal troops for evacuation and security efforts in the state.

While I have included some notable examples, this list does not include many times federal authorities have been mobilized in states or territories without state requests, including the Whiskey Rebellion, Utah War, Indian Wars (including Wounded Knee I and II), standoffs with various groups, raids on Black Panthers and other political organizations, etc.

> Congressional Research Service: The Use of Federal Troops for Disaster Assistance: Legal Issues (PDF)
> The New Yorker Comment by Nicholas Lemann: Insurrection
> Sen. Patrick Leahy: Insurrection Act information

The photos are from a set taken by my friend Eric during his September 2005 relief deployment to New Orleans with the 3-505 82nd Airborne.