On Wednesday, May 21, the U.S. Senate took a series of procedural votes that, depending on who you ask, either “cross[ed] a point of no return” in terms of the chamber’s filibuster or “preserv[ed] the Senate’s prerogatives.” How did we get to this point and what actually happened?

Under the Congressional Review Act (CRA), enacted in 1996, federal agencies are required to notify Congress when they issue a new rule. If Congress wishes to overturn that agency action, they can use special, expedited procedures to adopt a joint resolution of disapproval. These procedures protect the disapproval measures from filibusters in the Senate and are only available for a limited period of time after Congress is notified of the rule.

The CRA’s definition of a “rule” is, importantly, broader than the definition of what agency actions must go through the notice-and-comment process under the Administrative Procedure Act (APA). The CRA also, however, narrows the APA’s definition of “rule,” exempting rules of particular applicability, rules relating to agency personnel, and rules of “of agency organization, procedure, or practice that [do] not substantially affect the rights or obligations of non-agency parties.”

As Jesse Cross has documented, it became apparent soon after the CRA’s enactment that agencies were not necessarily reporting to Congress on every action that meets the definition of a “rule” under the law, potentially putting the legislative branch at a disadvantage. Could agencies simply hold back reports as a way of preventing the CRA’s expedited procedures from ever being triggered?

To address this problem, Congress developed an ad hoc workaround. If an agency takes an action but does not submit a report on it to Congress under the CRA, a member or committee can request an opinion from the Government Accountability Office (GAO) as to whether the decision in question constitutes a “rule” for the purposes of making available expedited procedures to overturn it. While the statute itself does not give this responsibility to GAO, it does implicate GAO in the broader CRA project, vesting it with the task of reporting to committees on major rules transmitted under the CRA. Involving GAO in this way is also, moreover, consistent with GAO’s general responsibility of advising Congress on questions related to appropriations law.

If GAO assesses an agency action that was not submitted by the agency as a rule to qualify as such under the CRA, the Senate’s parliamentarian defers to that interpretation and has enforced the publication date of the GAO opinion in the Congressional Record as the start date for the various CRA time periods (of which there are six separate ones). Members have sought these opinions from GAO more often in recent years than in the past. Between 1996 and 2006, GAO issued eight such opinions in ten years; in 2023 alone, it issued 13.

It is one of these opinions, sought by a senator from GAO, that was the first event in the chain of events that culminated in the recent adoption of a new Senate precedent. Under the Clean Air Act, California is eligible for a waiver of the Act’s preemption on states from enacting emissions standards. In 2019, the EPA had withdrawn a waiver to California for its Advanced Clean Car Program, but after a change in presidential administration, the agency rescinded the withdrawal of that waiver in 2022 by issuing a “notice of decision.” It did not submit that action to Congress as a rule under the CRA, leading Senator Shelley Moore Capito (R-W.V.) to seek an opinion on the decision’s status from GAO. In a 2023 opinion, GAO concluded that the notice was “an adjudicatory order not subject to CRA” and even if it were to satisfy the APA’s criteria for a rule, “it would be considered a rule of particular applicability, and, therefore, would still not be subject to the CRA’s submission requirement.”  

We might think the story would end there: agency performs action, GAO determines action is not a rule for the purposes of the CRA, and there is no opportunity to use the CRA’s expedited procedures. Fast forward fifteen months, however, and after another presidential transition, the EPA submitted to Congress, as rules under the CRA, three subsequent “notices of decision” related to California’s emissions waivers issued by the agency; one had been issued in 2023 and the other two in January 2025, just before the end of the Biden Administration.

The transmittal of these three notices in February 2025—which, notably, actually contained language indicating that their original drafters in the Biden Administration believed they were not rules under the CRA—prompted three senators (Sheldon Whitehouse (D-R.I.), Alex Padilla (D-Calif.), and Adam Schiff (D-Calif.)) to inquire with GAO as to whether they counted as rules and were thus eligible to be the subject of resolutions of disapproval considered under expedited procedures.

Note that this is the reverse of the situation in which GAO is usually consulted; senators ordinarily turn to GAO when something an agency has done has not been submitted as a rule but should have been. Here, senators were asking whether something that an agency had represented as a rule was, in fact, not one. Indeed, referencing a 2018 opinion involving IRS revenue guidance, GAO explained to the 2025 requesters that “GAO does not issue formal decisions on actions that agencies have submitted to Congress as rules under CRA because that submission generally obviates the need for a GAO decision on the matter.”

Because, however, of the existence of “prior [GAO] caselaw that addressed the applicability of CRA to Clean Air Act preemption waivers,” GAO explained that “the analysis and conclusions in our 2023 Clean Air Act preemption waiver decision would also apply to the Notices of Decision recently submitted as rules to Congress by EPA.” The Senate’s parliamentarian, following her past practice of deferring to GAO’s assessments of whether an action meets the definition of a rule, advised senators that resolutions of disapproval would not be eligible for expedited procedures.

Senate Republicans, then, were faced with a dilemma. Many clearly wanted to overturn the waivers, which would ban the sale of new gas-powered cars in California by 2035. But, according to press reports, some GOP senators were nervous about the prospect of explicitly ignoring or overruling the parliamentarian, whose status as a trusted, non-partisan, neutral arbiter of the Senate’s rules and precedents is important to the smooth functioning of the chamber. This took off the table, for example, having the presiding officer simply issue a ruling from the chair stipulating that the notices of decisions were in fact rules, since the parliamentarian had advised they were not.

That brings us to the events of May 21. To make it possible to consider resolutions of disapproval for the waivers under the CRA’s expedited procedures while still allowing some senators to claim that, arguably, they had not ignored the parliamentarian, Majority Leader John Thune (R-S.D.) engineered a series of procedural votes. First, he needed to clarify that points of order, or the ability to claim that a rule is being violated, were available under the Congressional Review Act. (The confusion here is at least plausibly real; one section of the law says that all points of order are waived, while another implies that rulings of the chair on points of order can be appealed.)

Under the Senate’s Rule XX, one option available to the chair for dealing with a point of order—though used infrequently, and usually for novel issues—is to put the question to the Senate for a vote rather than ruling on the question herself. Senator Capito, who was presiding, did just that. After alternating votes on motions to table from Thune and Senate Minority Leader Chuck Schumer (D-N.Y.) and a series of motions to recess and adjourn from Schumer, the Senate ultimately, by a vote of 51-46, established that points of order could be offered under the CRA. Armed with that precedent, Thune made a second point of order “that joint resolutions that meet all the requirements of section 802 of the Congressional Review Act or are disapproving of Agency actions which have been determined to be rules subject to the CRA by a legal decision from GAO are entitled to expedited procedures under the Congressional Review Act.” Capito again put the question directly to the Senate, and by another vote of 51-46, the point of order was sustained.

Where does that leave the Senate in the context of the CRA? With, it seems, two options for establishing that something is a rule for the purposes of the CRA. First, if an agency transmits an action to Congress purporting it to be a rule under the CRA, Congress can take that claim at face value and, subject to the CRA’s various deadlines, use expedited procedures to overturn it. The language of the point of order also appears, however, to preserve Congress’s ability to consult GAO in situations where an agency takes an action that constitutes a rule and does not send it over to Congress. In those scenarios, Congress may still ask GAO to weigh in and defer to its interpretation.

What about more broadly? Here, there are two different dimensions to consider. The first is how this change fits in with the broader discourse around the Senate filibuster. The Senate is on a slow march to majority rule, and each time it votes to expand the set of questions that are not subject to a potential filibuster, as they did here, we should consider that another step on that march. When the Senate reaches the end of that road in the future, the choice by a majority party to abolish the legislative filibuster will almost certainly involve a much larger policy objective than was at stake here, but every step taken is worth noting.

In addition, while Thune was careful to construct an approach that allowed some senators to save face on the most literal version of the question “did we overrule the parliamentarian?,” we shouldn’t ignore the broader context in which this move was executed—that is, a more general stress test on an important set of institutional norms. As Congress considers major legislation under the budget reconciliation process—which is also protected from the filibuster—the Senate has already chosen to side-step the parliamentarian once (by using a tactic that didn’t require consulting with her in a situation when they historically might have) and Thune will likely face some pressure to do so again.

The second dimension to consider involves the scope of additional actions that might now be available for Congress to overturn without the threat of a filibuster in the Senate, given that the chamber has established, firmly, that it can defer to the executive branch’s representation of whether something is a rule for CRA purposes. One could certainly imagine an administration—especially one with broad deregulatory interests, such as this one—wanting to use this tactic to allow swift congressional disapproval of a wide range of inherited actions it does not like. Using congressional disapproval under the CRA might be especially attractive, moreover, because the CRA contains a prohibition—albeit untested—on an agency issuing a rule that is “substantially the same” as one overturned by Congress under the CRA. But much depends on the political will of congressional Republicans and the role of other priorities that compete for attention, and only time will tell how broadly the new version of the tool gets used.

Molly Reynolds is a Senior Fellow in Governance Studies at the Brookings Institution.