President Donald Trump said on Monday that he will file a federal lawsuit aimed at overturning the Senate’s century-old “blue slip” practice, which lets home-state senators block presidential nominees for federal judgeships and U.S. attorney posts. Trump’s threat follows Sen. Chuck Grassley’s refusal to advance the nomination of Alina Habba as U.S. attorney for New Jersey after the state’s two Democratic senators withheld their blue slips. Constitutional and legal scholars warn the case faces long odds. Courts have repeatedly declined to interfere with congressional procedures, citing the Constitution’s grant of authority for each chamber to set its own rules and the Speech or Debate Clause. Supreme Court precedent in United States v. Ballin (1892) and Eastland v. U.S. Servicemen’s Fund (1975) suggests judges are unlikely to compel the Senate to act on nominations. The dispute underscores a wider confirmation stalemate. Roughly 145 Trump nominees are awaiting floor votes, and Republican leaders say they may change Senate rules or consider recess appointments if Democrats continue to slow the process. Majority Whip John Barrasso said Republicans will discuss unilateral rule changes when the chamber reconvenes next week, raising the prospect of a renewed institutional fight over advice-and-consent powers.