What powers does Trump have to send troops to cities — even if they don't want them?

President Donald Trump's order to deploy 2,000 California National Guard troops to Los Angeles to quell anti-immigration enforcement protests — without the consent of Gov. Gavin Newsom — is an extraordinary move, according to experts in national security and presidential powers.

Immigration and Customs Enforcement launched operations in L.A. last week, stretching into the weekend, arresting more than 100 people. Demonstrators protested the raids, clashing with police in the city and surrounding areas. Law enforcement has responded by shooting nonlethal, but dangerous, rubber bullets and pepper spray at protesters and journalists.

It is the first time since 1965 that a president called National Guard troops to respond to civil unrest without a governor's official request for assistance, according to Elizabeth Goitein, the senior director of the Brennan Center's Liberty and National Security Program.

She called such a move unprecedented.

"The conditions that would normally be present, and that should be present, for the president to deploy the military are simply not here," she said.

Trump's presidential memoranda argued that the National Guard deployment was necessary and defendable as these "violent protests threaten the security of and significant damage to Federal immigration detention facilities and other Federal property" and that the demonstrations "constitute a form of rebellion against the authority of the Government of the United States."

Additionally, on Monday, a defense official confirmed to NPR that 700 Marines based out of Twentynine Palms have been mobilized for L.A. and are expected to operate in a "support role" and perform the same duties as the National Guard.

California and Newsom have responded: Newsom announced on Monday that the state is suing the Trump administration over the president's decision. Newsom's office said in a statement that the lawsuit, which names Trump, Defense Secretary Pete Hegseth and the Department of Defense, alleges the National Guard order "violates the U.S. Constitution and exceeds" the president's authority.

So, what are the powers granted to the president of the United States to quell unrest? And how is the Trump administration bucking tradition and legal precedent in this situation?

A National Guard officer wearing a helmet with visor and a gas mask stands guard at the Metropolitan Detention Center during an anti-ICE protest in downtown Los Angeles on Sunday.

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What gives Trump authority to call up federal troops

Generally, federal troops are prohibited from using military force against civilians in normal law enforcement under the Posse Comitatus Act of 1878, according to Goitein.

The "extremely rare exception to this rule" is the Insurrection Act, a set of laws that give the president authority to use federal troops to quell civil unrest in a crisis, Goitein said. The Insurrection Act, which predates the development of modern state and local police departments, allows federal troops to engage in law enforcement activities, like searches, seizures and arrests.

This act has not yet been invoked by the White House in Los Angeles, despite the fact that Trump and his allies have referred to the protesters as "insurrectionists." Trump said on Sunday that so far he didn't see the basis for invoking the Insurrection Act, though he left open the possibility of doing that in the future.

In fact, the act has only been used 30 times in U.S. history, Goitein noted.

"It hasn't been used since 1992 and it hasn't been used without a state request," she said. Then-President George H.W. Bush last used it to tamp down violence in Los Angeles after a jury acquitted police officers in the beating of motorist Rodney King.

Instead of the Insurrection Act, Trump is relying on "an obscure statute that has never been used in the way that he is using it," Goitein said.

That little-used provision is "10 U.S.C. 12406," within Title 10 of the U.S. Code on Armed Services. It allows the president to deploy federal troops in instances of "a rebellion or danger of a rebellion" against the U.S. government.

Newsom's office said the president exceeded his "Title 10 authority, not only because the takeover occurred without the consent or input of the Governor, as federal law requires, but also because it was unwarranted."

And further, Newsom's office said Trump's move is illegal because "the unrest in Los Angeles is nowhere close to rising to the level of a 'rebellion' beyond the capacity of local and state authorities to control, nor is it different in kind from other similar situations in recent years that were brought under control by local authorities with no need for military intervention."

In the past, this provision has "been used along with the Insurrection Act," Goitein said. "It hasn't been used as a standalone authority, and whether it can provide on its own the substantive authority to do the things that President Trump is doing would be a question" for the courts, if it gets there.

Steve Vladeck, a Georgetown law professor, wrote on his Substack that invoking this provision doesn't authorize the National Guard troops to conduct their own immigration raids, arrests or do anything other than what the president's memo stated, which was to "ensure the protection and safety of Federal personnel and property."

A Waymo car burns in the street as smoke billows during protests in Los Angeles on Sunday. Following a series of aggressive federal immigration operations in the city, tensions escalated when ICE agents conducted a high-profile raid on a Home Depot location.

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A debated authority

The president is also justifying calling the military to L.A. by seemingly pointing to an implied authority in Article 2 of the Constitution, according to Christopher Mirasola, an assistant professor at the University of Houston Law Center.

This implied constitutional authority, called the protective power, is a debated theory of presidential power that says the president holds inherent constitutional authority to use the military to protect federal functions, properties and persons, Mirasola said.

Goitein noted this is not a new idea and has been put forward by the executive branch for many decades — including during Trump's first administration.

In the past, the Justice Department "has opined that when protecting federal functions and property, the military is not actually conducting law enforcement" and so the Posse Comitatus Act, which is supposed to block federal participation in law enforcement, simply doesn't apply, Goitein explained.

"The courts have not had the opportunity to resolve whether, under this theory, the military can perform these fundamental law enforcement functions that we're talking about in a situation like what's unfolding in Los Angeles," she said.

Protesters march during a 'Hands Off!' protest against the Trump administration on April 5 in Los Angeles.

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Why this could move beyond L.A.

Goitein and Mirasola are both closely watching how this conflict plays out.

"If the court tries to put constraints on what [Trump] can do under these authorities, I would fully expect that then his next step would be to invoke the Insurrection Act," Goitein said.

As of now, the actions of the National Guard are strictly limited to protecting the federal immigration officers, their actions and federal buildings.

"If we see the National Guard moving meaningfully beyond this more limited role, then we are certainly seeing an overstepping of the legal theory that's really at the foundation of the deployment in L.A.," Mirasola warned.

And that may happen given, in Mirasola's view, the presidential memorandum is extremely broad and, on its face, doesn't appear limited to L.A. In fact, "Los Angeles" is not explicitly stated in the memo's text and the secretary of defense is given wide latitude to issue military protective activities.

In fact, the memorandum also says, "The Secretary of Defense shall consult with the Attorney General and the Secretary of Homeland Security prior to withdrawing any personnel from any location to which they are sent."

"As protests continue and potentially expand over the coming days," Mirasola said, "I worry that there is going to be political pressure to move beyond the limited ambit of what's included in the protective power."
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