Note 45. The Senate’s Nuclear Option, 2025
When running for his leadership post, Senate Majority Leader John Thune (R-SD) promised to protect the right of a minority to conduct a “legislative filibuster.” This was in line with the long-held views of conservatives who wanted to preserve the right of minorities to filibuster and prevent expansion of federal programs. For Thune, a legislative filibuster involved a piece of legislation—a bill or a resolution—but not nominations, which the Senate considers in “executive session.” So, for Thune, the precedents set in 2013, 2017, and 2019, which reduced the threshold for cloture from a three-fifths majority to a simple majority on nominations and cut the time permitted on post-cloture debate on nominations, should not be extended into the realm of legislation. Developments in 2025 put into question Thune’s commitment.
Essential Background
The traditional way of changing a Senate rule is to adopt a resolution making the change. A resolution may be subject to a minority filibuster, preventing a vote on the resolution, unless a supermajority (now three fifths, or 60 votes) approves a cloture motion. Historically, the supermajority threshold made it difficult to adopt a rule that advantaged the majority over the minority.
The nomination precedents of 2013, 2017, and 2019 were accomplished by use of the “nuclear option.” That’s the informal term invented in the 1990s to refer to use of a path to changing a rule that circumvents a filibuster and puts a majority in control. It involves a point of order that a simple majority can invoke cloture for some purpose even when the plain meaning of the written rule is that a three-fifths majority is required. The presiding officer either rejects the point of order or leaves the issue for the Senate to decide. In the former case, a senator can appeal the presiding officer’s ruling and then the matter is settled by a simple-majority vote. In the latter case, the matter also is settled by a simple-majority vote. In this way, the majority can create a precedent directly contrary to the standing rule without touching the standing rule.
In the 1990s, then-Majority Leader Trent Lott (R-MS) predicted that such a move by him to overcome minority filibusters would lead the minority to “go nuclear.” By calling for votes and refusing unanimous consent on minor matters, regularly conducting extended debate, and offering motions to interrupt the flow of business, the minority could bring the Senate to a crawl. A few years later, however, majority leaders got serious about the nuclear option and eventually used it to adopt precedents that a simple majority was the cloture threshold for nominations and debate on nominations for lesser posts was limited to two hours.
Recent Developments
On three occasions in 2025 so far, Democrats rightly argue, Thune has edged over the line from nominations to legislation in their use of the nuclear option.
A May episode concerned the application of the Congressional Review Act (CRA), which allows simple majorities in the House and Senate to overturn a federal rule or regulation by passing a joint resolution. At issue was the EPA waivers that allowed California’s stricter auto emission standards. Republicans ignored some legislative history, a GAO opinion, and the parliamentarian’s view that a waiver to a rule was not itself a rule subject to the CRA. If the waiver is not a rule, the waiver could be overturned by Congress only with a new bill, which would have been subject to a Democratic filibuster and 60-vote cloture. The majority Republicans proceeded anyway, but they sought to avoid entertaining a point of order on which the presiding officer would be expected to follow the guidance of the parliamentarian. Instead, Thune made a point of order to interpret the CRA to permit simple-majority action on blocking the waivers. He arranged for the presiding officer to make no ruling and instead submit the question to the Senate for a majority vote, which Thune knew the Senate would uphold his point of order (he voted against it), as it did, 51-46.
A new precedent was set, the Democrats properly warned, that a myriad of non-rule actions by the executive branch would be subject to the CRA, at least in the Senate. Moreover, they insisted, the CRA provided for joint resolution, which has the effect of law and surely is “legislative.” Democrats added that, in approving Thune’s expansion of CRA coverage to executive actions that were not formally designated rules or regulations, Thune was breaking his promise not to use the “nuclear option” to affect legislation. The nuclear option, of course, refers to setting a precedent to change the plain meaning of a Senate procedural rule by a point of order (subject to simple majority approval) rather than changing a Senate rule directly by resolution (subject to a filibuster and 60-vote cloture). It is “reform-by-ruling,” I once called it, setting a precedent inconsistent with the plain mean of the written rule.
In June, Thune and Senate Republicans returned to circumvention of the parliamentarian and acquiring Senate approval of a longstanding rule change by precedent. The issue was whether tax cuts that needed to be renewed must be viewed as deficit-causing if renewed or, contrary to the Byrd rule and decades of precedent, could be counted as a continuation of existing policy, a difference with mammoth consequences for the bottom line of the Republican reconciliation bill. Again, rather than have a senators make a point of order and the presiding officer rule following the guidance of the parliamentarian, Thune made a point of order and had the presiding officer submit the question to the Senate without ruling himself. Thune’s Republicans backed him, “nuking” the longstanding rule, and setting up Republican claims of a much smaller deficit generated by the bill than was obviously true.
By September, Republicans became impatient with Democratic efforts to slow action on presidential nominations to executive branch posts by demanding votes on cloture and the nominations repeatedly. They sought action on a resolution—called an “executive resolution” in this case because of its effect on procedure in executive session--that provided for considering nominations en bloc when in executive session. Democrats blocked action on the resolution so Republicans responded by seeking to nuke the requirement for a 60-vote majority to stop a filibuster and force a vote on the resolution. Democrats indicates a willingness to devise compromise provisions for the resolution, but Republicans obviously were eager to proceed by nuking supermajority cloture for the resolution.
In this case, Thune did not seek to circumvent the parliamentarian and made a point of order that “the threshold for cloture on an executive resolution for the en bloc consideration of nominations…is a simple majority.” The presiding officer, taking the recommendation of the parliamentarian, rejected the point of order and Thune appealed to the Senate, which settled the matter by a simple majority vote. Thune had the votes so the Senate’s standing rule providing for a three-fifths majority threshold for cloture was set aside and a simple majority was allowed to approve cloture on the resolution.
On October 1, failure of Congress to pass appropriations bills or a continuing resolution (CR) caused a government shutdown, which lasted for weeks. The apparent hold up was the Senate, where Democrats could block spending bills, but the House had managed to pass only three of the regular 12 appropriations bills. Within days, legislators and outsiders began to speculate that Senate Republicans would eventually nuke the supermajority requirement for cloture, at least for a CR, to gain Senate adoption of a House-passed CR and end the shutdown. About a week into the shutdown, Majority Leader Thune explained why he and his Republican colleagues opposed nuking the filibuster for legislation by observing that “if the Democrats had won the majority [in the 2024 elections], they probably would’ve tried to nuke the filibuster. And then you’d have four new senators from Puerto Rico and DC, you’d have a packed Supreme Court, you’d have abortion on demand.”
The implicit claim was that Democrats would use simple majorities to create two new states that would elect Democrats to the Senate, produce a liberal Court, and eliminate obstacles to abortion. Thune could have consider nuking the filibuster just for a CR or appropriations bills, but he certainly was concerned about setting a precedent that would be a big step in the direction of simple majority cloture for all legislation.
There are several features of these episodes worth emphasizing.
First, some Republicans were reluctant to directly and conspicuously reject a recommendation of the parliamentarian so Thune found a way to avoid having the presiding officer make any ruling. By September, no Republicans were publicly expressing misgivings about overturning a ruling based on the parliamentarian’s recommendation.
Second, the CRA and executive resolution episodes concerned more than the application of the Senate’s cloture rule as applied to nominations. Both involved legislation—a joint resolution of disapproval and a simple resolution. Republicans may have rationalized that these were very narrow nuclear option applications, but these developments did set limitations on legislative filibusters, at least in certain cases.
Third, the reconciliation case showed future majorities how to bulldoze the Byrd rule and related precedents without engaging the parliamentarian. This may be the move Republicans eventually regret most.
Fourth, the Senate has given up on using supermajority thresholds to give the 60th senator the power to insist on a modicum of moderation in presidential appointments and, now it seems, even the reconsideration of executive branch actions that are not regulations. If courts and administrators make policy—and they do—the Senate has rejected that principle for more than a slice of federal policy making. Action by a majority is deemed more important than delay and compromise. The Senate leaves supermajority rule for policy making involving appropriations bills and legislation that does that does not significantly affect spending and revenues.
Finally, Republicans are strongly committed to supermajority cloture for legislation in order to protect party and conservative interests on key issues of lasting importance, such as the composition of the Senate and the Court. For the time being, they are willing to protect those interests even at the expense of other legislative objectives that are at least temporarily obstructed by the minority.
Time to Revisit Senate Rules
Renewal and revision of the Senate’s rules are long overdue. The Senate should undertake a comprehensive renewal of its rules. This renewal should involve a reassessment of committee utilization, agenda setting, daily operations, and the processes for approving legislation and presidential nominations. The goal should be to limit the minority’s ability to obstruct action, ensure minimal opportunities for senators and minority parties to propose alternatives, revitalize committee functions, encourage deliberation, and enhance staff support.
Fifteen years ago, I wrote about the "Senate syndrome," characterized by minority party obstructionism led by party leaders, and the majority party’s efforts to curtail the minority’s parliamentary options. This obstruct-and-restrict cycle created deep frustration among senators. Since then, the Senate’s condition has deteriorated further. The diminished use of committees and expert staff, fewer floor amendments, near-universal obstructionism, and the significant wastage of time on the Senate floor are now commonplace. Entire sessions are squandered on strategizing ways to exploit or circumvent rules, representing a gross misuse of public resources. The Senate is massively failing to serve America’s needs.
It is well understood that the combination of supermajority thresholds, intense partisanship, and narrow majority parties has rendered the Senate a legislative killing machine. While many reformers focus on reducing partisanship, the problem extends beyond the last few decades of heightened partisanship. Currently, the Senate operates under a disjointed mix of thresholds for acting on legislation and nominations. With the nuclear option—allowing a simple majority to overrule the presiding officer for simple-majority cloture—majorities have set simple majority thresholds for cloture on nominations and resolutions for groups of nominations. Simple majorities can overturn federal regulations under the Congressional Review Act, approve officer status for recent West Point graduates, and pass reconciliation bills entailing extensive policy changes in federal spending and revenues. Yet, a bill to designate my birthday as a federal holiday or to fund the DOD or HHS can be filibustered and passed only with a three-fifths majority. There is no governing logic to this mix of rules, just a hodge-podge of rules from a long series of choices, sometimes made by majorities but sometimes imposed by minorities, made for a variety of reasons.
The Senate can fix this. Although many rules are built into statutes, the Senate may act to supersede or reinterpret those rules. Recent precedents surrounding the nuclear option demonstrate that a majority can interpret its rules as it sees fit.
What should and can be done? These reforms might include mandating that floor amendments be germane, ensuring amendment opportunities for both majority and minority senators, limiting debate on motions to proceed and amendments, reducing the number of executive positions requiring Senate confirmation, improving background check processes, and possibly requiring 41 senators to oppose cloture for debate to continue. We might add for a new process for considering a presidential nomination when the nomination is reported from committee with bipartisan support. Numerous steps can be taken that fall short of an overhaul of the cloture process.
In the interest of accountability, I advocate rules that allow a majority to act. Senator Jeff Merkley’s proposal is a good place to start. But without going that far creative senators can further improve appropriations, budget, and nomination processes in ways that would garner broad approval. At a minimum, I would expand simple-majority rule to spending and debt limit bills, federal election issues, and, perhaps, a bill designated by each party in each Congress. I also would limit debate on post-passage motions, improve funding for committee staff and congressional support agencies, and create some time each month for debate on an issue selected by the two leaders or bipartisan select committee. There are so many possibilities for improvement.
When and How?
How should the Senate craft a reform package? One approach is to establish a bipartisan select committee or even a commission—including former senators and external experts—to propose reforms. A select committee’s recommendations could be considered in a fast-track process for the current Senate to approve or reject by a simple majority. Unless the Senate decides otherwise, these reforms might include a provision that they take effect at least six years in the future, following the conclusion of all senators’ current terms. This is a meaningful step because the Senate treats its rule as permanent until changed. Of course, a future Senate would retain the authority to block the implementation of these new rules if necessary.
Such a process makes today’s senators anxious. Nearly all of them like Senate traditions that permit them to speak and offer amendments more freely than in the House and most American legislatures. The problem is that those Senate traditions have almost evaporated. The 2025 developments in the use of the nuclear option speed up the trend of nuking rules that serve those traditions and should make senators aware that this trend is unlikely to be reversed while they are in the Senate.
We should be demanding a renewal of the Senate that serves the long-term interests of the nation. Would the current Senate overcome a filibuster to initiate a reform process of this kind? I’m not optimistic; a majority might agree that supermajority cloture on a change in the rules should be nuked. We all should insist that the two leaders champion the cause and a bipartisan group of senators start the process.