As polls indicate Democrats could take back the US House of Representatives, and possibly the Senate, lawmakers are gearing up to investigate the Trump administration. But that may prove to be a difficult task, even with a majority in both chambers of Congress.

In late September, the Government Accountability Office (GAO) released a report on Elon Musk’s so-called Department of Government Efficiency titled “DOGE: Congress and the Public Lack Assurance That Systems and Data Were Protected at Multiple Agencies.” In it, the GAO revealed that multiple executive branch agencies had refused to fully cooperate with investigators about the extent and nature of DOGE’s access to sensitive systems and information. The Consumer Financial Protection Bureau (CFPB), which DOGE and the Trump administration gutted in the early months of the president’s second term, sent GAO a letter accusing investigators of bias and alleging the report was “misleading.”

The report, just the latest example of the Trump administration seeking to dodge congressional oversight, raises questions about what—if any—avenues the legislature has to enforce accountability, or even access basic information about what the government has been doing.

“In a world where there is no shame, it’s hard to think of what Congress can do that doesn’t involve some coercion of some kind,” says Emily Berman, a law professor at the University of Houston. “Like withholding money or going to court.”

The GAO serves as Congress’ primary investigative body; its work is most often initiated by requests from Congress, but it is independent and nonpartisan. It does not, however, have the ability to enforce laws or take on prosecution. Federal agencies don’t necessarily have to enact the agency’s suggestions, but they are legally required to cooperate with GAO’s requests for information and auditing.

The GAO and a Democratic congressional aide who spoke to WIRED on the condition of anonymity, though, say that the agencies investigated by the GAO for the DOGE report—the CFPB, the Department of Veterans’ Affairs (VA), the Department of Education, the National Oceanic and Atmospheric Administration (NOAA), the Securities and Exchange Commission (SEC), and the Small Business Administration (SBA)—all, in one way or another, refused to cooperate with the investigation.

“We have experienced increased challenges in obtaining information from agencies over the past year and a half,” GAO spokesperson Sarah Kaczmarek says. “As this report demonstrates, when agencies do not provide requested information, it can limit GAO’s ability to provide Congress and the public with assurance that federal programs, systems, and information are appropriately managed and protected.”