Appropriations law, which governs the spending of federal funds and the timing of that spending, exists in a unique space. A sub-section of administrative law, its disputes are not frequently brought under judicial review, but political review. This is driven by the relationship between the Congress, the appropriator of funds, and the President, the executor of appropriated funds. These two branches have come to rely on a little-known support agency to provide expertise and oversight over the complexity of appropriations law: the Government Accountability Office (GAO).
The GAO and its History
Congress created the GAO via the Budget and Accounting Act of 1921, though at the time it went by the name of “General Accounting Office.” This act imbued the GAO with a strong degree of independence as an agency, directed by a Comptroller General, and its original purpose was to help oversee the massive increase in spending during World War I. The Act’s language, requiring the Comptroller General as the head of GAO “investigate, at the seat of government or elsewhere, all matters relating to the receipt, disbursement, and application of public funds, and make to the President … and to Congress … reports and recommendations looking to greater economy or efficiency in public expenditures,” still underpins the GAO’s duties, purposes, and obligations.
The Comptroller General is entirely unique in the method of their appointment to the role, a process designed to highlight the independence and nonpartisan nature of the position. When the Office of the Comptroller becomes vacant, Congress establishes a commission to recommend nominees to the President for the President to then nominate for the advice and consent of the Senate. The commission consists of the Speaker of the House, the President Pro-Tempore of the Senate, the Majority and Minority Leaders of the House and Senate, the Chair and Ranking Members of the Senate Homeland Security and Government Affairs Committee, and the Chair and Ranking Members of the House Committee on Oversight. This commission must recommend at least 3 individuals to the President and then the President must select one of the recommended individuals to nominate for confirmation by the Senate.
While there are various legal challenges possible on this unusual appointment procedure, its design demonstrates that the Comptroller General was envisioned as someone both parties in both Houses of Congress and the President could accept and trust to be impartial in their work, unlike the expectation for a cabinet secretary. Reflecting this, the newly retired Comptroller General, Gene Dodaro, served in the role from 2008-2025, under four presidents: two Democrats and two Republicans.
The GAO and Appropriations Law
The GAO, through its role in auditing and reviewing spending issues, is typically tasked with determining whether an agency can spend a given amount of money it wants to at a given time it wants to in a way that it wants to. These are known as “amount, time, and purpose” requirements. To help agencies and Congress understand the answers to these questions, the GAO carries out a series of related duties. It publishes a multi-volume treatise on appropriations law known as “The Red Book” to inform the public, Congress, and agencies. It also provides trainings on appropriations law to congressional and agency staffers.
Most consequently, it issues formal decisions on appropriations law at the request of Congress or Agencies seeking to ensure that appropriations law is being correctly followed. Since 31 U.S. Code § 3526 (b) states that the GAO’s decisions on appropriations law are “conclusive,” many seek out the GAO to seek approval before doing something that risks being overturned later or putting them in legal jeopardy: once the GAO has ruled on the legality of a certain appropriation issue, the matter is settled and final. This “conclusivity” power enshrined in law provides weight to GAO’s decisions on appropriations law, strengthening its oversight.
The GAO and Oversight of Appropriations Law
To demonstrate the process GAO takes in their oversight function, take one GAO appropriations decision, titled “U.S. Capitol Police—Availability of Appropriations for Local Lodging of Employees,” published on August 14, 2025 as an example. This request was made by the U.S. Capitol Police themselves under 31 U.S.C. § 3529 to ask the GAO to issue a decision on whether the Capitol Police Board has the authority to permit the expenditure of appropriated funds to address a staffing shortage. Specifically, USCP sought to use the funds to pay for local lodging of DPD agents who were working overtime hours with less than 8 hours of rest between shifts.
Once the GAO received this request, or any other request, their standard practice is to contact the relevant agency to seek factual information and hear their legal views on the issue. Here, the USCP was the relevant agency and they included a factual background and their legal view in their request, seeking GAO’s confirmation as to the validity of their theory.
Then, the GAO applies the statute in question, guided by prior GAO decisions and customary agency practice. In this case, that meant interpreting the terms “meals and refreshments” before “and other support and maintenance” to indicate that USCP is also allowed to provide lodging in association with emergency situations, because such provisions are meant to provide “sustenance and comfort.” The GAO noted that this is only allowed in emergency situations, according to the statute in question, and recommended safeguards be put in place to ensure lodging is provided only in such situations. These recommendations are another part of how the GAO influences oversight over appropriations. What the GAO cannot do themselves, they frequently recommend to the agency as a best practice, and agencies frequently incorporate those recommendations.
Finally, the GAO concluded, assuming the facts provided by USCP in their request were accurate, that the USCP was authorized to provide lodging for those overtime agents. This assumption of facts is an important caveat for the GAO to state, given that if they approve the use of funds, they cannot reverse their own decision if new facts come to light. They can, however, reverse an outcome rooted in mistaken fact.
However, the most important appropriations law decisions made by GAO are not in response to a request made by either Congress or an agency, but rather are taken on by the GAO independently pursuant to their statutory requirement under the Congressional Budget and Impoundment Control Act of 1974 (ICA) or the Anti-Deficiency Act. These laws require and direct the GAO to issue reports when certain triggering events occur, whether or not there has been a specific request made. This was designed to allow the GAO to undertake and act upon them independently and immediately. However, independence and immediacy are where the GAO encounters its greatest limitations too.
Limitations on Oversight of Appropriations Law
The GAO’s role is to support Congress, including Congress’s constitutional authority over appropriations. However, perhaps based on view that the GAO, as a support agency to Congress, should not act against the Congress’s wishes, even to protect its own authority, the GAO under Comptroller General Dodaro never exercised its most powerful appropriations oversight mechanism.
The ICA contains a provision, 2 U.S. Code § 687, that allows the Comptroller General file suit in federal court over a violation of the ICA to restore illegally impounded funding. In the recent DC Circuit Court of Appeals case Global Health Council v. Donald J. Trump, the Court held that only the Comptroller General has standing to sue over ICA violations. In order to provide effective oversight and accountability over appropriations law, the GAO must take that next step to enforce the findings of its decisions in federal court.
If they do not, they are allowing Congress to abandon its constitutional authority over to the Executive, violating the nondelegation doctrine recognized by the United States Supreme Court in J. W. Hampton, Jr. & Co. v. United States, 276 U.S. 394 (1928) and upheld as recently as 2025 in Federal Communications Commission v. Consumers’ Research, 606 U.S. ___ (2025).
Conclusion
The GAO has a unique role and responsibility in government over appropriations law and its oversight, from writing much of the law itself, to educating those in government who practice it, to overseeing its implementation with comprehensive, authoritative, and legally binding decisions.
However, its slowness or unwillingness to act during an era of increasingly flagrant violations of appropriations law has made the GAO appear like an old organization unprepared for new challenges. Long-serving Comptroller General, Gene Dodaro, retired at the end of 2025. If Congress is looking for one action they can take to protect its constitutional authority relative to its political cost to Congress in opposing the Executive, recommending only Comptroller General candidates that are willing to assert the GAO’s oversight role in federal court using the ICA is it.