HJL,
The Posse Comitatus Act of 1878 (Pub. L. 18 USC P 1385) was supposed to keep the U.S. Military from enforcing local and federal law, or assisting local law enforcement in that duty. Well before the Posse Comitatus Act was passed, Congress passed the Insurrection Act of 1807 (Pub. L. 10 USC 331 thru 335), which was a “set of laws that govern the ability of the President to deploy U.S. troops on American soil.” Such deployment could only come at the request of a governor of the state in which an event was taking place requiring a larger military force. This all changed after Hurricane Katrina, where the Louisiana governor did not request federal troops to restore order. Congress went ahead and modified the Insurrection Act as follows:
“Section 1076 of the law changed Sec. 333 of the ‘Insurrection Act,’ and widened the President’s ability to deploy troops within the United States to enforce the laws. Under this act, the President may also deploy troops as a police force during a natural disaster, epidemic, serious public health emergency, terrorist attack, or other condition, when the President determines that the authorities of the state are incapable of maintaining public order. The bill also modified Sec. 334 of the Insurrection Act, giving the President authority to order the dispersal of either insurgents or ‘those obstructing the enforcement of the laws.’ The law changed the name of the chapter from ‘Insurrection’ to ‘Enforcement of the Laws to Restore Public Order.'”
The Insurrection Act is the most important legal authority for the President to authorize the use of federal troops to enforce the law. The Insurrection Act (there is really no single ‘Insurrection Act’ per se, but this name has been applied collectively to the four statutes noted below) consists of four statutes enacted at different times for different reasons that, when considered as a whole, provide the power that Presidents have used many times as the legal basis for using troops to enforce the law. The four sections of the act are as follows:
• Title 10, Section 331 was enacted in 1792 in response to challenges to the taxing power of the federal government. It allows the President, at the request of a governor or state legislature, to put down an insurrection by calling into federal service sufficient militia to “suppress the insurrection.”
• Title 10, Section 332 was enacted in 1861 at the outset of the Civil War. It allows the President to use the armed forces to enforce the laws or suppress a rebellion whenever, in his opinion, unlawful obstructions, combinations, or assemblages or rebellion against the authority of the United States make it impractical to enforce the laws using the course of judicial proceedings.
• Title 10, Section 333 was enacted in 1869 during the Reconstruction Era. It allows the President to use the armed forces or militia to respond to insurrection, domestic violence, unlawful combination, or conspiracies that prevent a state government from enforcing the laws.
• Title 10, Section 334 was enacted in 1861. It prescribes that the President shall issue a proclamation calling on insurgents to disperse before using the militia or armed forces to enforce the law.
The Insurrection Act is the most sweeping authority for the President to authorize and order the use of the federal troops for domestic operations. The President may not act on warning or even at the start of an incident, but must wait until the governor or a state legislature asks for federal assistance. This tends to discourage advance preparations and movements of troops-although Presidents have authorized such actions. This tiered approach in which the federal government acts only after local and state governments have failed, was workable when the cost of delayed response was acceptable, but it is inappropriate for the current situation.
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