The Constitution of the United States provides two exceptions for which the Posse Comitatus Act does not apply. These exceptions are based upon the inherent right of the U.S. government to ensure the preservation of public order and to carrying out governmental operations within its territorial limits by force, if necessary. These two exceptions are—
Emergency authority. A sudden and unexpected civil disturbance, disaster, or calamity may seriously endanger life and property and disrupt normal governmental functions to such an extent that local authorities cannot control the situation. At such times, the federal government may use military force to prevent the loss of life or wanton destruction of property and to restore government functions and public order. In these circumstances, federal military commanders have the authority, in extraordinary emergency circumstances where prior authorization by the President is impossible and duly constituted local authorities are unable to control the situation, to engage temporarily in activities that are necessary to quell large-scale, unexpected civil disturbances (see DODD 3025.18).
Protection of federal property and functions. When the need for the protection of federal property or federal functions exists, and duly constituted local authorities are unable to, or decline to provide adequate protection, federal action, including the use of military forces, is authorized.
2-9. Laws passed by the U.S. congress include four exceptions to the Posse Comitatus Act. With the first three laws discussed below (10 USC 331–333) there is a prerequisite that the President must take personal action, including the issuance of a proclamation calling upon insurgents to disperse and retire peaceably within a limited time. The four exceptions, based on law are—
10 USC 331. When a state is unable to control domestic violence and they have requested federal assistance, the use of the militia or Armed Forces is authorized.
10 USC 332. When ordinary enforcement means are unworkable due to unlawful obstructions or rebellion against the authority of the United States, use of the militia or Armed Forces is authorized.
10 USC 333. When a state cannot or will not protect the constitutional rights of the citizens, due to domestic violence or conspiracy to hinder execution of State or Federal law, the use of the militia or Armed Forces is authorized.
House Joint Resolution 1292. This resolution directs all departments of the U.S. government, upon request of the Secret Service, to assist in carrying out its statutory duties to protect government officials and major political candidates from physical harm.
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