President Donald Trump has intensified pressure on Senate Judiciary Committee Chairman Chuck Grassley to abandon the Senate’s 100-year-old “blue slip” courtesy, calling the practice “old and outdated” and urging the Iowa Republican to tell Democrats “to go to hell.” The custom allows home-state senators to block district-court and U.S.-attorney nominees by withholding a signed blue form. Trump argues the veto is enabling Democrats to stall nominees such as former campaign lawyer Alina Habba, tapped to become U.S. attorney for New Jersey, and says he is prepared to sue on constitutional grounds. Grassley and most Senate Republicans are refusing to yield. Grassley responded on social media that the practice has served conservatives, noting that during President Biden’s term Republicans used blue slips to keep “30 liberals off the bench that President Trump can now fill with conservatives.” Senate Majority Leader John Thune, along with Sens. Thom Tillis, Lisa Murkowski and John Kennedy, warned that scrapping the tradition could backfire on the GOP when it is again in the minority. Although Republican leaders are weighing procedural changes after Democrats slowed consideration of Trump’s nominees earlier this year, they say any fast-track plan would stop short of ending blue slips. The standoff underscores an unusual public rift between the president and his party over control of judicial and prosecutorial appointments as the Senate heads into its fall session.