The James H. Shannon Building (Building One) on the NIH campus in Bethesda, Maryland. (Photo by Lydia Polimeni,/National Institutes of Health)

President Donald Trump’s freeze on $8 billion of congressionally appropriated funding to the National Institutes of Health was illegal, the Government Accountability Office reported Tuesday.

Orders Trump signed in the early days of his return to office and related administration directives violated the Impoundment Control Act by failing to spend money that Congress, which holds the power of the purse under the Constitution, had approved, the GAO report said.

Roughly 1,800 grants for health research were held up by the administration, the report said.

Trump’s Inauguration Day order ceased funding for a variety of health research grants that related to diversity, equity and inclusion, transgender issues or environmental harms. The Department of Health and Human Services issued a memo directing its agencies, including NIH, to cease publishing notices in the Federal Register of meetings of grant review boards.

GAO, an independent investigatory agency that reports to Congress, called those meetings “a key step in NIH’s grant review process.” HHS has since restarted notices of the meetings.

From February to June, the NIH released $8 billion less than it obligated in the past two years, representing a drop-off of more than one-third, according to the GAO. The gap between 2025 spending and that of previous years continued to grow, GAO said, with NIH obligating a lower amount of grant funding each month.

Illegal impoundment

The failure to fund grant awards violated the Impoundment Control Act and the Constitution, which certified Congress as the branch of government responsible for funding decisions, said GAO.

If a law is passed by Congress and signed by a president, it must be carried out by the executive branch, the watchdog said.

“The President must ‘faithfully execute’ the law as Congress enacts it,” the report said. “Once enacted, an appropriation is a law like any other, and the President must implement it by ensuring that appropriated funds are obligated and expended prudently during their period of availability unless and until Congress enacts another law providing otherwise. … The Constitution grants the President no unilateral authority to withhold funds from obligation.”

There are specific circumstances that allow for a funding freeze — a rescissions law, such as the one Congress passed last month to defund public broadcasters and foreign aid, is one example — but they did not apply to this case, the GAO said.

Delays may be permissible to allow a new presidential administration to ensure grants are awarded based on its priorities. But a complete block on funding is illegal, the GAO said. There is no evidence that other grant awards — or any other type of funding at HHS — took the place of the $8 billion in unspent grant money, the report said.

“While it can be argued that NIH reviewed grants to ensure that funds were spent in alignment with the priorities of the new administration, NIH did not simply delay the planned obligations of the funds,” the GAO said. “Rather, NIH eliminated obligations entirely by terminating grants it had already awarded.”

GAO can sue the executive branch based on its findings. The report noted there is already litigation from other parties over the frozen grants.

Dems call for reinstatement

Congressional Democrats responded to the report by harshly criticizing Trump and White House Office of Management and Budget Director Russ Vought and calling for the funds’ release.

“This is simple – Congress passed and the President signed into law investments in NIH research to help find cures and treatments for cancer, Alzheimer’s disease, ALS, diabetes, mental health issues, and maternal mortality,” U.S. House Appropriations Committee ranking Democrat Rosa DeLauro of Connecticut said in a statement. “But now, GAO has determined that President Trump and OMB Director Vought illegally withheld billions in funding for research on diseases affecting millions of American families—research that brings hope to countless people suffering.”

Senate Appropriations Vice Chair Patty Murray, a Washington state Democrat, said in a statement the funding freeze “dangerously set back” efforts to cure cancer, Alzheimer’s and other diseases.

“Today’s decision affirms what we’ve known for months: President Trump is illegally blocking funding for medical research and shredding the hopes of patients across the country who are counting on NIH-backed research to propel new treatments and cures that could save their lives,” Murray said. “It is critical President Trump reverse course, stop decimating the NIH, and get every last bit of this funding out.”

An HHS spokesperson deferred a request for comment Tuesday to OMB.

An agency investigated by the GAO is generally given a draft of the watchdog’s findings and asked to respond.

The HHS response, obtained by States Newsroom, said grant reviews were back on schedule, though it did not address grant obligations.

“Despite the short delay in scheduling and holding peer review and advisory council meetings to allow for the administration transition, NIH has been on pace with its reviewing grant applications and holding meetings and has caught up from the pause when compared to prior years,” the response said.

GAO’s summary of the HHS response said the department had restarted meetings of grant review boards and provided some “factual information” but did not justify the lack of grant spending or provide current status of payments for previously approved grants.