Senate Parliamentarian Rejects Additional GOP Border Security Reconciliation Provisions — Republicans Race to Rewrite Before May 18 Floor Vote as Byrd Rule Challenges Mount

The Senate Parliamentarian continued issuing Byrd Rule rulings on May 15, 2026, rejecting additional provisions from Republicans' $71.7 billion immigration enforcement reconciliation package ahead of the scheduled May 18 Senate floor vote. The rulings follow the initial Byrd Rule strike on May 14 targeting main border patrol funding, DHS appropriations, and border security/technology/screening sections. Senate Republicans must rewrite challenged provisions with new language that passes Byrd Rule scrutiny — provisions must be primarily budgetary in nature, within the committees' jurisdiction, and not incidental to non-budgetary policy. Senate Democrats have systematically challenged each section. The Parliamentarian's decisions create a compounding procedural problem: with Trump's June 1 signing deadline looming and Senate committee markups scheduled for May 19, Republicans have very little time to revise language and resubmit for Parliamentarian review. The procedural hurdles do not block reconciliation outright — Republicans could override the Parliamentarian's rulings by majority vote — but Senate Majority Leader John Thune has indicated he will not pursue that approach. Some conservative senators have called for overriding the Parliamentarian, which Senate Democrats say would 'break the Senate.' The $71.7B package, if enacted without the struck provisions, would be substantially reduced in scope; estimates suggest the struck provisions account for tens of billions in the total package. Trump had staked significant political capital on completing the bill by June 1.