The Insurrection Act is a federal law that allows the president to deploy the military and National Guard troops to suppress civil disorder, insurrection or rebellion. It was last used by President George H. W. Bush during the Los Angeles riots after the Rodney King verdict in April 1992.

Gavin Newsom asked the Trump administration on Sunday to rescind its move to deploy 2,000 California National Guardsmen to Los Angeles to subdue immigration protests, accusing the White House of illegally overriding his authority and intentionally inflaming tensions with protesters.

Trump has sent National Guard troops to Los Angeles to quell protests over federal arrests of undocumented individuals, with about 300 troops arriving on Sunday. This is the first time a president has sent the National Guard to a state without the governor’s request since the 1960s.