The Supreme Court on Oct. 29, 2024. (Photo by Jane Norman/States Newsroom)

Every state with either a Democratic governor, attorney general or both signed a brief to the U.S. Supreme Court, asking the justices to side with Illinois and Chicago to continue blocking President Donald Trump’s proposed deployment of National Guard troops to Chicago.

In an amicus brief filed Monday in the Trump administration’s appeal to overturn lower courts’ rulings that Trump lacks the legal authority to send troops to Chicago, 24 Democratic officials argued that restraining presidential power to mobilize National Guard troops was an essential constitutional safeguard.

“The President has asserted a boundless power far out of step with our Nation’s laws and tradition: the power to federalize and deploy unlimited numbers of National Guard troops at his whim and without any judicial review,” they wrote. “This Court should not endorse such a power.”

State National Guard units are generally under the control of the state’s governor. Federal law does allow the president to federalize state National Guard units in rare cases of invasion, insurrection or when the state is unable to enforce federal laws. 

The Trump administration has argued that circumstances in Chicago constitute both the threat of an insurrection and the inability of local police to enforce federal law.

Illinois Gov. JB Pritzker and Chicago Mayor Brandon Johnson have argued that lower courts correctly decided that those circumstances were not met in Chicago and Trump may therefore not deploy troops to the city.

Maryland Attorney General Anthony G. Brown and Washington state Attorney General Nicholas W. Brown led the brief. 

Attorneys general in Arizona, Colorado, Connecticut, Delaware, Hawai‘i, Maine, Massachusetts, Michigan, Minnesota, Nevada, New Jersey, New Mexico, New York, North Carolina, Oregon, Rhode Island, Vermont, Wisconsin and the District of Columbia also signed on, as did the governors of Kansas, Kentucky and Pennsylvania. 

California Gov. Gavin Newsom, a Democrat whose state led its own lawsuit against Trump’s deployment of National Guard troops and U.S. Marines to Los Angeles, filed a separate amicus brief Monday.

The U.S. Department of Justice did not respond to a request for comment Tuesday.

Tussle over Chicago

The case stems from Trump’s order to federalize Illinois National Guard troops and deploy them to Chicago. 

Trump has said the move is needed to control crime that threatens federal personnel and buildings. Pritzker and Johnson, as well as the state officials in Monday’s brief, say the use of military forces to respond to routine crime is a gross violation of the U.S. Constitution’s balance of powers.

The states, even where Trump has not threatened to send troops, are in danger of losing the power granted to them by the Constitution, the officials wrote. 

“President Trump’s invocation of 10 U.S.C. § 12406 to deploy armed, federalized National Guard soldiers and entangle them in everyday civilian law enforcement activities like responding to small-scale protests—over the objection of Illinois’s Governor—is a stunning break from law and tradition,” they wrote, referring to the law outlining the conditions under which a president may federalize a state National Guard.

High court appeal

U.S. Solicitor General D. John Sauer filed the Trump administration emergency motion for a stay Friday. He argued that an injunction from Illinois federal court on Oct. 7 wrongfully decided the scope of the president’s power to control National Guard units.

Sauer argued for a broader interpretation of Trump’s authority, saying the president alone could determine if the conditions for federalizing National Guard units had been met.

“The district court’s injunction impermissibly substitutes the court’s own judgment for the President’s on military matters and rests on a construction of Section 12406 that would render the statute a virtual nullity,” Sauer wrote in the Oct. 17 motion. “The injunction improperly impinges on the President’s authority.”

The Democratic officials on Monday called the assertion of such authority an overreach of presidential power.

“Allowing the President to commandeer state National Guards and use them at his whim would fundamentally upset the balance of power between States and the federal government,” they wrote. “This Court should decline Defendants’ invitation to take such an unprecedented and drastic step.”

Illinois Gov. JB Pritzker speaks at a news conference in Chicago on Oct. 6, 2025. Chicago Mayor Brandon Johnson stands at right. (Photo by Scott Olson/Getty Images)

A federal judge will hear arguments Thursday in Illinois over Chicago’s lawsuit challenging President Donald Trump’s deployment of National Guard troops to the state before deciding whether to block the move, the judge wrote in an order.

In a one-paragraph order, U.S. District Judge April M. Perry, whom Democratic President Joe Biden appointed to the bench, set an 11:59 p.m. Wednesday deadline for the Trump administration to respond in writing to the suit filed by the Democratic leaders of Illinois and its largest city, which they filed Monday morning. 

Perry did not immediately grant the restraining order Gov. JB Pritzker and Mayor Brandon Johnson sought to block the deployment at the outset of the case.

Perry said she expected the federal government’s response to include evidence about when National Guard troops would arrive in Illinois, where in the state they would go and “the scope of the troops’ activities” once there. She set oral arguments for 11 a.m. Central Time on Thursday.

The suit seeks to stop Trump’s federalization of Illinois National Guard and mobilization of Texas National Guard troops to the state. Texas Gov. Greg Abbott, a Republican, has also agreed to send Guard troops to Portland, Oregon, at Trump’s request.

Pritzker and Johnson’s complaint calls the federalization of state National Guard troops “illegal, dangerous, and unconstitutional.” The Democrats added that the move was “patently pretextual and baseless,” meaning it could not satisfy the legal requirements for a president to wrest from a governor control of a state’s National Guard force.

Pritzker, appearing at a Tuesday event in Minneapolis with Minnesota Gov. Tim Walz said the federal government has been noncommunicative about the plan for the National Guard troops, but had received “reports” that troops have arrived at a federal facility in the state.

“We don’t know exactly where this is going to end,” he said. “What we know is that it is striking fear in the hearts of everybody in Chicago.”

A federal judge in another case blocked the deployment to Portland after city and Oregon leaders sued to stop it. The federal government appealed that order, and a panel of the 9th Circuit U.S. Court of Appeals will hear oral arguments Thursday, according to a scheduling notice posted Tuesday.

Insurrection Act cited by Trump

Trump has said the extraordinary use of troops, which raises serious legal and constitutional questions about the line between military forces and domestic law enforcement, is necessary to control crime in some Democrat-led cities, including Chicago and Portland. 

State and local leaders in those jurisdictions, as well as Los Angeles, have said military personnel are not needed to supplement local police. Pritzker called the proposed deployment to Chicago an “invasion.”

Trump indicated Monday he may seek to further escalate the push for military involvement domestically, saying he would have no qualms about invoking the Insurrection Act, which expands presidential power to use the military for law enforcement.

“We have an Insurrection Act for a reason,” he told reporters. “If I had to enact it, I’d do that. If people were getting killed and courts were holding us up or governors or mayors were holding us up, sure, I’d do that.”

Democratic U.S. Sens. Tammy Duckworth and Dick Durbin of Illinois, Jeff Merkley and Ron Wyden of Oregon and Alex Padilla and Adam Schiff from California — the three states where Trump has sent troops over the governors’ objections — called on Trump to withdraw the troops in a Tuesday statement that warned of the escalating conflict between blue states and the federal government.

“Donald Trump is stretching the limits of Presidential authority far past their breaking point and moving us closer to authoritarianism with each dangerous and unacceptable escalation of his campaign to force federal troops into American communities against the wishes of sovereign states in the Union he is supposed to represent,” the senators wrote.

Dems in Congress question raid

Trump’s use of National Guard troops is in part a response to protests in Democratic cities over this administration’s crackdown on immigration enforcement.

Trump has surged immigration enforcement officers to certain cities. Those agents have pursued sometimes aggressive enforcement, including a Sept. 30 raid on a Chicago apartment building that has been criticized for using military-style tactics.

A group of eight U.S. House Democrats wrote Monday to Attorney General Pam Bondi and Homeland Security Secretary Kristi Noem calling for an investigation into that raid.

The members were Homeland Security Committee ranking member Bennie Thompson of Mississippi, Judiciary Committee ranking member Jamie Raskin of Maryland, J. Luis Correa of California, Pramila Jayapal of Washington, Shri Thanedar of Michigan, Mary Gay Scanlon of Pennsylvania and Delia Ramirez and Jesús “Chuy” Garcia of Illinois.

“We write to express our outrage over the immigration raid,” they said. “Treating a U.S. city like a war zone is intolerable.”

J. Patrick Coolican contributed to this report.