Senate Majority Leader John Thune has confirmed that the Senate will not challenge the advice of the Senate Parliamentarian, Elizabeth MacDonough, which has significantly impacted the GOP’s ambitious domestic-policy bill. This decision came after MacDonough ruled that key provisions of the bill would not comply with budget reconciliation rules, thereby exposing the legislation to potential Democratic filibusters.

The parliamentarian's decisions have stirred considerable controversy among Republicans. After the rulings were announced, figures like Rep. Greg Steube (R-Fla.) and Sen. Tommy Tuberville (R-Ala.) vocally criticized MacDonough, denouncing her as a symbol of the bureaucratic "swamp." Their frustration underscores the political tension surrounding the bill, notably provisions aimed at modifying Medicaid funding rules and restricting public benefits for undocumented residents.

Despite these criticisms, Thune stated that overruling the parliamentarian would not be a viable strategy for advancing the legislation. MacDonough, who has more than 25 years of experience in the Senate and has served under both Republican and Democratic majorities, plays a crucial role in interpreting Senate rules concerning budget reconciliation. This process allows certain bills to be passed with a simple majority, circumventing the need for a supermajority to overcome a filibuster.

The GOP’s strategy relies heavily on this process to pass their so-called "One Big Beautiful Bill" without Democratic support. However, the reconciliation rules restrict the content of such bills to primarily fiscal matters, a limitation that has previously thwarted attempts to include broader policy changes.

Historically, the role of the Senate Parliamentarian is advisory, meaning that her interpretations can be overruled or she could be replaced. However, such actions are rare and are generally avoided to maintain Senate norms and the integrity of procedural rules.

The decision to adhere to MacDonough's guidance reflects a broader bipartisan desire to preserve these norms, despite the immediate legislative setbacks it may cause for the GOP. This restraint highlights the complex interplay between party ambitions and institutional precedents in the U.S. Senate.