Explainer: is it legal for Trump to use US troops to suppress protests?

Irish Times

a day ago

In a rare use of military force on domestic soil, the Trump administration has
deployed national guard troops and active-duty Marines in Los Angeles
to respond to protests set off by its immigration crackdown.
US president
Donald Trump
has long mused about using military force on domestic soil to crush violent protests or riots, fight crime and hunt for migrants living in the country illegally – a move that his aides talked him out of during his first term. Between his two presidencies, he said he would do so without the consent of state governors if he returned to the White House.
The state of California and its governor,
Gavin Newsom
, filed a lawsuit on Monday night seeking to overturn Trump's move, calling it an unnecessary provocation and unlawful.
Here is a closer look.
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What did Trump's order do?
Trump called up national guard troops to be put under federal control, issuing an order late on Saturday that authorised defence secretary
Pete Hegseth
to use them to protect immigration enforcement agents, buildings and functions from interference by protesters. As justification, the White House cited recent protests against Immigration and Customs Enforcement (ICE) raids in Los Angeles.
The order called for at least 2,000 troops to be deployed for at least 60 days. Trump also authorised Hegseth to use regular federal troops 'as necessary' to augment the work of the federalised national guard units.
The national guard consists of military forces in the state, largely part-time troops who have separate, full-time civilian jobs. Normally, each state's governor controls its own guard, directing it to deal with a disaster or civil disorder. But under certain circumstances, federal law allows the president to take control.
Los Angeles County sheriff's deputies clash with protesters in Compton on Saturday. Photograph: Philip Cheung/The New York Times
On its face, deploying active-duty troops into an American city is an escalation because they fight war full time and, unlike a national guard, may come from anywhere around the country. Legally, both federalised national guard forces and active-duty troops are federal troops, under the control of the defence secretary and the president.
What are the rules of engagement?
This is unclear.
For now, the federalised troops appear to have limited authority, Stephen I Vladeck, a Georgetown University law professor, wrote in analysing the order over the weekend. It says the troops can protect ICE agents and federal buildings against attacks by protesters, but it does not authorise them to carry out immigration raids or police the city's streets in general.
But Trump's order did not specify any standards for when troops would be able to use force – such as arresting people or shooting them – if his administration deemed a protest to threaten federal personnel, property or functions.
Notably, Hegseth has railed against military lawyers who promoted what he saw as unduly restrictive rules of engagement aimed at protecting civilians in war zones. He has fired the top judge advocate general lawyers who give advice on legal constraints. And his remarks since Saturday have not signalled restraint.
On social media, Hegseth called protests against ICE in Los Angeles 'violent mob assaults' intended to prevent the removal of migrants living in the country illegally who he said were engaged in an 'invasion.'
Police fill the street as they face off with protesters in Los Angeles, California on Sunday. Photograph: EPA
Hina Shamsi, director of the American Civil Liberties Union National Security Project, said on Sunday that 'no matter who carries the gun or what uniform they wear, it's important to remember that the constitution – and in particular the First Amendment – applies and troops' conduct is governed by strict constitutional limits.'
Is it legal to use federal troops on US soil?
Usually it is not, but sometimes it can be.
Under an 1878 law called the Posse Comitatus Act, it is normally illegal to use federal troops on domestic soil for policing purposes. But an 1807 law, the Insurrection Act, creates an exception to that ban for situations in which the president decides that 'unlawful obstructions, combinations or assemblages, or rebellion against the authority of the United States' make it 'impracticable' to enforce federal law.
Trump's order criticised the protests as violent and said they threatened to damage federal immigration detention facilities. 'To the extent that protests or acts of violence directly inhibit the execution of the laws,' it added, 'they constitute a form of rebellion against the authority of the government of the United States.'
But he did not invoke the Insurrection Act.
What legal authority did Trump cite?
Trump invoked a statute, Section 12406 of Title 10 of the US code, that allows him to call national guard members and units into federal service under certain circumstances, including during a rebellion against the authority of the federal government.
The call-up statute does not, on its face, appear to confer any authority to use any kind of federal troops – whether they be federalised national guard members or active-duty Marines – in the ways Trump has authorised.
But Trump also referred to 'the authority vested in me as president by the Constitution,' which may suggest his administration believes he can claim inherent constitutional power as the commander in chief to use troops on US soil in those ways.
During the Vietnam War, William Rehnquist, then a lawyer for the justice department before being confirmed to the US supreme court, wrote memos for its office of legal counsel saying that presidents had inherent power to use troops to prevent anti-war protesters from obstructing federal functions or damaging federal property in the District of Columbia and at the Pentagon.
Using troops in such a protective capacity would not violate the Posse Comitatus Act, Rehnquist argued at the time. But there was no definitive court test of that idea. Moreover, the nation's capital and the campus of the Pentagon are both federal enclaves, unlike the businesses in Los Angeles where ICE agents are carrying out raids.
Must a state's governor consent to federal troops?
Not always.
But Section 12406 says that orders for national guard call-ups 'shall be issued through the governors of the states.' One of the state's complaints is that Hegseth ignored that provision, notifying the general in charge of California's national guard without going through Newsom.
The Insurrection Act would provide a separate basis for federalising California's National Guard or for using active-duty troops without going through a governor. California attorney general Rob Bonta said on Monday that his office had been studying that law should Trump try to invoke it, but he insisted that local authorities were 'completely prepared' to address any developments.
Protesters confront police near a US Immigration and Customs Enforcement facility in San Francisco. Photograph: Loren Elliott/The New York Times
Using federal troops on domestic soil outside military bases for policing purposes has happened only in rare and extraordinary circumstances, and doing so over the objection of a state's governor is even more unusual.
The last time a president used federal troops for domestic policing purposes was in 1992, when then president George HW Bush invoked the Insurrection Act to suppress widespread riots in Los Angeles after a jury acquitted police officers who had been videotaped beating a black motorist, Rodney King. But in that instance, California's governor, Pete Wilson, and Los Angeles' mayor, Tom Bradley, asked for federal assistance.
Presidents have not used federal troops without the permission of state governors since the Civil Rights Movement, when Southern governors defied court orders to desegregate state schools.
Which troops is Trump using?
For now, the national guard troops have come from the California National Guard, while about 700 Marines joining them are normally based at Twentynine Palms in California, said US northern command.
But Trump directed Hegseth to 'co-ordinate with the governors of the states' – plural – in identifying which units to call into federal service. That raises the possibility that Hegseth could send troops from a Republican-controlled state, further heightening the political tensions.
Another possibility is that the administration envisions expanding the use of troops to other parts of the country. Trump's order is not limited to Los Angeles, stating instead that troops must protect immigration enforcement operations at any 'locations where protests against these functions are occurring or are likely to occur.'
What is the status of the court challenge?
California filed a lawsuit on Monday evening. It argued that the Trump administration had violated the procedure required by the National Guard call-up statute in bypassing Newsom.
It also argued that local law enforcement could handle policing the protests, and by sending federal troops into the fray, Trump was impeding states' rights protected by the 10th Amendment. It reserves to the states those governing powers that the constitution does not bestow on the federal government.
The US justice department has not yet responded to the lawsuit and declined to comment.
As events unfold, there could also be lawsuits on behalf of protesters, invoking individual rights such as First Amendment protections for freedom of speech and assembly.
This article originally appeared in
The New York Times
.
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