Defense Support of Civil authorities

Defense Support of Civil Authorities (DSCA) is the process by which United States military assets and personnel can be used to assist in missions normally carried out by civil authorities. These missions have included: responses to natural and man-made disasters, law enforcement support, special events, and other domestic activities. A recent example of the use of DSCA is the military response to Hurricane Katrina. DSCA is the overarching guidance of how the United States military can be requested by a federal agency and the procedures that govern the actions of the military during employment.

The "Directorate of military support" (DOMS) for domestic operations (DOMS) who is the functional process manager of DSCA is located inside each state's "Joint Operation Center" (JOC). The normal course of action is for the Office of Emergency Management within the state to request military support through the JOC. In turn, the JOC under the authority of the DOMS will initiate military support in the form of equipment that supports the Federal Emergency Management Agency (FEMA) Emergency Support Functions.

The provision of DSCA is codified in Department of Defense Directive 3025.18. This directive defines DSCA as:

"Support provided by U.S. Federal military forces, National Guard, DoD civilians, DoD contract personnel, and DoD component assets, in response to requests or assistance from civil authorities for special events, domestic emergencies, designated law enforcement support, and other domestic activities. Support provided by National Guard forces performing duty in accordance with Reference (m) is considered DSCA, but is conducted as a State-directed action also known as civil support."

There are numerous other directives, policies and laws that shape the militaries role in conducting operations in support of other federal agencies. Some of them are the Insurrection Act, Homeland Security Act, Stafford Act, Economy Act and the Homeland Security Presidential Directive – 5. Each of these affect the way the military responds to a request for assistance from an interagency partner.

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