The U.S. Supreme Court has agreed to hear a significant case for the future of America's democracy. In the case of Trump v. Illinois, the Court will decide whether the president can federalize and deploy the National Guard in Illinois and Chicago.

Early last month, officials in Illinois, particularly in Chicago, filed a federal lawsuit to block the federal government's plan to deploy National Guard troops within the state. A federal district court judge in the Northern District of Illinois issued a temporary restraining order on Oct. 9, 2025, prohibiting the Trump administration from federalizing and deploying the National Guard within Illinois.

In Los Angeles and Portland, federal district judges issued similar orders blocking troop deployment after determining that protests did not rise to the level of a rebellion and that local law enforcement officials currently were capable of enforcing the law, but the U.S. Court of Appeals for the Ninth Circuit stayed the orders.

The Northern District of Illinois found the Trump administration had "made no attempt to rely on the regular forces before resorting to federalization of the National Guard," and it had not contended "(nor is there any evidence to suggest) that the president is incapable with the regular forces of executing the laws."

The Trump administration argued there is "no reason to believe that courts can, or should, second-guess the President's conclusion" that military force is needed to suppress an emergency. "(T)his case," the brief argues, falls in the heartland of unreviewable presidential "discretion." According to the SCOTUSBlog, even if judicial review is permissible, the government says, a court must be "highly deferential" to the president's decision.

The Seventh Circuit Court of Appeals upheld the district court's order finding insufficient evidence of a rebellion and that the administration was unlikely to succeed at trial. The Trump administration appealed to the U.S. Supreme Court, requesting an emergency stay to allow the Illinois deployment to proceed. The high court did not stay the order but agreed to hear the case.

With a ruling pending, the Supreme Court requested supplemental briefs from both parties on a specific legal question: how the term "regular forces" in 10 U.S.C. 12406, the law relied on by the Trump administration to deploy National Guard troops, should be interpreted and how that interpretation affects the application of the law.

Congress first delegated its constitutional power to activate state militias to the president through the Militia Act of 1792. Congress renewed that delegation of authority in the Militia Act of 1795. The 1795 Act was a precursor to the Militia Act of 1903. Like Section 12406, the 1795 Act contained a predicate "invasion" condition: "(W)henever the United States shall be invaded, or be in imminent danger of invasion ... , it shall be lawful for the president of the United States to call forth such number of the militia ... as he may judge necessary to repel such invasion."

According to Democracy Docket, "The (Supreme Court's) question appears to stem from an amicus brief filed with the Supreme Court by Martin Lederman, a former DOJ deputy assistant attorney general who's now a professor at the Georgetown University Law Center."

Lederman argued that "regular forces" does not refer to federal law enforcement — ICE, FBI, border patrol— but rather the armed forces within the "Department of War," formerly the Department of Defense.

Lederman noted, according to Democracy Docket, that throughout U.S. history, and specific legal history of 10 U.S.C. 12406, "regular" was often used as a shorthand for the Army — "the regulars" — as opposed to the state militias that evolved into today's National Guard.

The argument goes, since the Trump administration never sent members of the armed forces to assist ICE in Chicago, we do not know if the administration could determine that it was unable to execute federal law with "regular forces" as required by Section 12406 and "therefore lacked the authority to federalize members of the Illinois Guard, Lederman asserted."

With the Supreme Court's new briefing schedule, we can expect a decision as soon as the end of the month.

Matthew T. Mangino is of counsel with Luxenberg, Garbett, Kelly & George P.C. His book The Executioner's Toll, 2010 was released by McFarland Publishing. You can reach him at www.mattmangino.com and follow him on Twitter @MatthewTMangino

Photo credit: Aaron Burden at Unsplash