Senate Judiciary Chairman Chuck Grassley has accused two Democratic senators from Washington state of withholding blue slips on a judicial nominee for political reasons.

Grassley on Thursday fired off a letter to Sens. Patty Murray and Maria Cantwell claiming they blew off officials from the Trump White House who reached out regarding the nomination of Perkins Coie partner Eric Miller to the U.S. Court of Appeals for the Ninth Circuit.

“I will not allow senators to abuse the blue-slip courtesy by withholding the blue slip for political or ideological reasons,” Grassley wrote. “This is particularly important for circuit-court nominees, who are nominated to regional courts that affect states, not just the home-state senators' states.”

“It is a President's prerogative to select his preferred judicial nominees for the Senate to consider. And it is your prerogative to vote against the nominee on the Senate floor if you do not think the nominee is qualified,” Grassley wrote. “But there are 98 other senators who also should have the opportunity to vote on this judicial nominee.”

Spokesmen for Murray and Cantwell didn't immediately respond to requests for comment on Friday.

Miller is among four Trump administration judicial nominees slated for a confirmation hearing on Oct. 24, as Republicans on the Senate Judiciary Committee move ahead on the president's court picks while Congress is in recess. Miller, who was nominated to the Ninth Circuit in July, has been a partner at Seattle-based Perkins Coie since 2012, heading the firm's appellate practice. He has argued 16 cases before the U.S. Supreme Court, according to his firm bio, including some during his stint in the U.S. solicitor general office between 2007 and 2012. Miller also previously clerked for U.S. Supreme Court Justice Clarence Thomas and Judge Laurence Silberman of the D.C. Circuit.

This isn't the first time Grassley has clashed with Democratic senators from the Pacific Northwest over one of the president's Ninth Circuit nominees. Oregon's two Democratic U.S. senators—Ron Wyden and Jeff Merkley—initially refused to return blue slips on the nomination of Assistant U.S. Attorney Ryan Bounds because he wasn't vetted through their bipartisan selection committee. They continued to withhold their blue slips even after their selection committee found him qualified after questions arose about his controversial undergraduate writings. The Bounds nomination was ultimately withdrawn in July just before a full Senate vote was scheduled as reports surfaced that he didn't have enough support to pass.

Read Grassley's letter on the Miller nomination:

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