They argue that absent confirmation — which Senate Democrats do not have the votes for — the White House is circumventing time limits on interim leadership imposed by the 1998 Vacancies Reform Act.

The Biden administration has pointed to a separate statute that allows the deputy Labor secretary to fill in “until a successor is appointed.” Su served as deputy under Walsh.

The findings: GAO, in a five-page report, sided squarely with the later interpretation of federal law.

“[W]e conclude that Ms. Su is lawfully serving as the Acting Secretary,” the GAO stated in a five-page report. “We also conclude that the Vacancies Act’s time limitations on acting service do not apply to the Acting Secretary’s service.”

Why it matters: GAO is the body tasked with policing violations of the Vacancies Reform Act, which periodically trips up presidents of both parties but saw several high-profile instances during the Trump administration.

The agency’s findings will surely be used by DOL to defend against potential legal challenges to major regulatory actions taken under Su, such as its recently proposed expansion of overtime eligibility or forthcoming changes to the standards on independent contractor classification.

DOL declined a request to comment on GAO’s findings.

What’s next: GAO opened the review in July in response to a request from House Education and the Workforce Chair Virginia Foxx (R-N.C.), one of the most vocal critics of Su and the Biden administration’s labor agenda.

Republicans have proposed multiple bills designed to prevent a similar situation to Su’s from arising in the future, which Foxx pointed to following the report’s release.

“Despite not having the votes to be approved by the Senate, the Biden administration is keeping anti-worker Julie Su installed as the head of the Department of Labor,” Foxx said in a statement. “This situation is depriving Congress of its role in providing advice and consent on nominees, and it should never happen again.”