On Monday, in response to riots across the United States that were sparked by the death of a black man, George Floyd, while a police officer knelt on him, President Trump announced that he would use the U.S. military to stop the riots.
Washington, D.C.’s Metropolitan Police Department fired smoke devices outside of the White House to push protestors back, as Trump told reporters and others present in the Rose Garden that he is, “Mobilizing all available federal resources, civilian and military, to stop the rioting and looting, to end the destruction and arson and to protect the rights of law-abiding Americans, including your Second Amendment rights.”
He urged governors to deploy the National Guard in numbers so that they “dominate the streets,” and went on to say, “If a city or state refuses to take the actions necessary to defend the life and property of their residents, then I will deploy the United States military and quickly solve the problem for them,” and referred to himself as “your president of law and order and an ally of peaceful protestors.”
For a president to do this without the request of a state’s governor, whose general right is to have the authority to maintain order within state borders, the president needs to formally invoke a group of statutes known as the Insurrection Act. In law, the principle of this act is reflected in a law called the Posse Comitatus Act, and it makes a general prohibition on the military from participating in domestic law enforcement.
Only during times when domestic insurrection hinders the normal enforcement of U.S. law is the president allowed to invoke the Insurrection Act.
The Insurrection Act has been put into action dozens of times since it was made into law in the early 1800s but it has only been used once since the civil rights movement in the 1960s. This was in 1992 when the acquittal of four white Los Angeles police officers for the beating of a black motorist, Rodney King, led to mass rioting and looting in L.A. and other cities across the United States.
President Trump has yet to formally invoke this act and send federal troops to a state that feels they are unnecessary but historically, courts have been reluctant to second-guess a president’s military declarations.