An independent federal watchdog has opened more than three dozen investigations into the Trump administration to determine if it has illegally withheld billions of dollars in congressionally approved funds, raising the odds of a high-stakes constitutional clash over the power of the government’s purse.
The acknowledgment by the Government Accountability Office came on Tuesday, as House and Senate Democrats estimated for the first time that President Trump might have blocked the delivery of at least $430 billion during his first 100 days in office. That imperiled money enacted for foreign aid, green energy, health and transportation-related programs, potentially in violation of the law.
The dispute originates in Mr. Trump’s vast, chaotic and continued reconfiguration of the federal government. Since the first days of Mr. Trump’s term, he and his top advisers — including the tech billionaire Elon Musk — have shuttered programs while blocking or slowing a wide array of funds seen as wasteful, unnecessary or incompatible with the president’s broader political agenda.
Many Democrats and legal scholars contend that Mr. Trump’s budget maneuvers violate the Constitution, which vest the powers to tax and spend with Congress, not the executive branch. The spending interruptions have also prompted a wave of court challenges as state officials, nonprofits and other federal aid recipients say the White House has acted illegally.
On Tuesday, Gene L. Dodaro, the comptroller general of the Government Accountability Office, revealed at a congressional hearing that his office had opened “39 different investigations” into the administration. He suggested some of the focus was on cuts or changes to spending at the Education Department, the Environmental Protection Agency and other major federal offices.
Under a 1970s law, the Government Accountability Office has the power to investigate whether an administration has improperly withheld authorized funding in defiance of Congress. The watchdog has the power to sue if it finds the administration illegally impounds funds.
Mr. Dodaro did not signal how his office might proceed. He told lawmakers that some federal agencies had not been “responsive” to his requests for information, while the White House’s budget office had largely ignored his entreaties.
“We’re trying to get information from the agencies about what their legal position is for not expending the money,” Mr. Dodaro said.
He acknowledged the inquiries after questioning from Senator Patty Murray, Democrat of Washington, who leads her party on the chamber’s top appropriations panel. Earlier on Tuesday, Ms. Murray and her counterpart in the House, Representative Rosa DeLauro, Democrat of Connecticut, issued the estimate that more than $400 billion in congressionally-appropriated funds had been slowed or blocked under Mr. Trump.
At the hearing, Ms. Murray faulted Mr. Trump for having “unilaterally frozen” funds in ways that “wreaked havoc for our families and communities across the country.”
A spokeswoman for the White House budget office did not immediately respond to a request for comment. The Government Accountability Office declined to comment further.
The inquiries seemed to raise the likelihood of a legal showdown between Mr. Trump, congressional Democrats and the Government Accountability Office, a powerful yet little-known independent watchdog. The office has largely remained unscathed even as the president has taken aim at other areas of oversight, including firing ethics officials such as the nation’s inspectors general.
At the heart of the battle is the president’s ability to invoke a power known as impoundment, which would allow Mr. Trump to stem the flow of federal dollars even if Congress instructs otherwise. Mr. Trump and his top budget adviser, Russell T. Vought, argue that a decades-old law restricting impoundment is unconstitutional, maintaining instead that the president should possess expansive authorities to reconfigure federal spending.
“The president ran on the notion that the Impoundment Control Act is unconstitutional,” Mr. Vought told lawmakers at a confirmation hearing this year, referring to the 1970s law that specifies controls over the president’s spending powers. “I agree with that.”
Mr. Vought similarly encouraged Mr. Trump to impound federal funds during his first term. In a legal memo issued at the end of the administration, Mr. Vought wrote at the time that existing law “limits the executive branch’s ability to spend appropriations effectively.”
But the matter most notably came to a head in 2020, during Mr. Trump’s impeachment trial, when the Government Accountability Office found that the administration had violated the law by withholding roughly $400 million in aid to Ukraine in defiance of Congress. Mr. Vought defended his office’s actions at the time. In January, he told lawmakers that the administration had “engaged in a policy process” and ultimately released the funds “by the end of the fiscal year.”
The dozens of new investigations are set to proceed as Mr. Trump prepares to issue his budget for the 2026 fiscal year, which is expected to propose deep cuts to many domestic programs, including child care, education, health and housing initiatives targeting the poor.
The president is expected to couple that blueprint with a formal, legal request to Congress to cancel spending previously authorized for the current fiscal year, predominately targeting billions of dollars in foreign aid and money for public broadcasting.