Blue slips: The document senators use to approve judicial picks that has Trump attacking Grassley

President Donald Trump has railed against Sen. Chuck Grassley (R-IA) for maintaining the customary use of blue slips in judicial nominations.

Grassley, chairman of the Senate Judiciary Committee, has backed and advocated the continued use of blue slips. The committee typically does not advance judicial nominations unless both senators representing the state where that judge would be located return blue slips approving their nomination.