U.S. President Donald Trump arrives at the White House in Washington, D.C., U.S., October 5, 2025. REUTERS/Aaron Schwartz

By Bo Erickson and Courtney Rozen

WASHINGTON (Reuters) -President Donald Trump has repeatedly tested the boundaries of executive power since his return to office and is exploring uncharted legal territory with threats to carry out mass firings during the federal government shutdown, legal experts and lawmakers said.

The Republican president this year has aggressively pursued cuts to the federal government and has repeatedly raised the prospect of using the shutdown, now in its seventh day, as justification for permanent layoffs. But his administration has not acted on it.

That, experts said, may be because neither federal courts nor the federal employee board that oversees workers has determined whether federal agencies may permanently cut staff during a shutdown.

"We are in largely uncharted territory," Nick Bednar, a University of Minnesota professor who is an expert in administrative law, said this week.

Since 1981, the U.S. has had 15 federal government shutdowns that furloughed hundreds of thousands of workers. But no president has sought to use a shutdown as the basis for large-scale firings.

Whether courts would back Trump’s reasoning depends on how they interpret the Antideficiency Act, an 1884 law that requires a shutdown when Congress has not approved funding — an authority the Constitution assigns to the legislative branch.

Trump took office pledging to remake and sharply reduce the federal government, and his administration has already moved to force out some 300,000 workers this year.

It has sent mixed signals about plans to cut staff during the shutdown. Trump said on Sunday that layoffs were taking place "right now." But White House Press Secretary Karoline Leavitt said the next day he was referring to workers furloughed since funds expired on October 1 — a temporary, unpaid leave rather than permanent job losses — and that the administration was still considering the permanent cuts.

“There are some legal questions about that that are unresolved,” said Senator Gary Peters of Michigan, the top Democrat on the Senate panel that oversees government affairs.

"I think the courts will make a determination," said Senator Mike Rounds, a Republican appropriator from South Dakota, "The president is going to do whatever he can to push whatever issues he believes appropriate to get past this impasse."

The White House and Office of Management and Budget did not respond to requests for comment.

POTENTIAL LEGAL LIABILITY

Two large unions representing federal employees, AFGE and AFSCME, filed a lawsuit that seeks to block the administration from laying off workers during a shutdown. They argued the 1884 law bars such firings because the planning and administrative work they require are not permitted under its narrow exemption for activities to preserve “life and property.”

The White House has offered a range of reasons for the potential firings. Leavitt recently told NPR’s "Morning Edition" the goal is to “cut back to save money in a responsible way that respects the American taxpayer's money, especially when we are in this financial crunch right now.”

Bednar, the law professor, said precedent gives federal agencies “broad discretion” to invoke mass layoffs – called reductions in force – in response to budget shortfalls, and federal courts could extend that discretion to shutdowns.

But Emory University appropriations law Professor Matthew Lawrence said any official who approves mass firings outside the Antideficiency Act’s legal parameters could face felony liability.

“Presumably, right now, there are officials within government trying to ask OMB why they think this is legal, and can they provide enough assurance that the agency doesn’t have to worry about violating the law and the Constitution,” Lawrence said.

No one has ever been prosecuted under the law, he added, but violations remain subject to a five-year statute of limitations.

APPEALS FOR FEDERAL WORKERS HIT BY TRUMP CHANGES

If the Trump administration does fire federal workers during the shutdown, those employees can appeal, federal employment attorneys said.

One avenue is the Merit Systems Protection Board, a panel that reviews appeals from federal workers who believe they were terminated because of their political views or other reasons spelled out in the law.

But Matthew Biggs, president of a union that represents 6,500 NASA employees, said the administration had “gutted the very institutions” that federal employees would normally turn to. The board can issue initial decisions but lost its quorum in the spring to decide appeals, in part because Trump fired a member appointed by former President Joe Biden.

Biggs said his union's "fundamental issue" in the shutdown fight is whether lawmakers take steps to guard money approved by Congress from attempts by the administration to use it in ways other than intended.

Another path for federal employees is to dispute how they were fired. Civil service law requires agencies to prepare a detailed list of positions targeted for cuts, taking into account factors such as location and employee tenure. Agencies can take weeks or months to tick off the steps, according to the non-partisan Partnership for Public Service.

"It's difficult to imagine that these agencies believe that it wouldn't be challenged,” said Michelle F. Bercovici, a federal employment attorney, about potential firings.

(Reporting by Bo Erickson and Courtney Rozen, additional reporting by David Morgan and Daniel Wiessner; editing by Scott Malone and Cynthia Osterman)