Oregon’s two Democratic senators are blocking one of President Trump’s judicial nominees with claims that a “longstanding” state tradition mandating that nominees be chosen from their “judicial selection committee” was violated, but the tradition they cite has never applied to picks for the U.S. Circuit Court, according to records viewed by the Washington Free Beacon.

Sens. Ron Wyden and Jeff Merkley alerted the White House that they would be blocking the nomination of Oregon native Ryan Bounds for a seat on the U.S. Circuit Court of Appeals for the Ninth Circuit. Bounds is currently serving as assistant U.S. Attorney for the District of Oregon.

“We cannot return a blue slip on any judicial nominee that has not been approved by our bipartisan judicial selection committee,” the senators wrote in a letter to the White House referencing the informal “blue slip” process by which senators are able to block nominations of judges from their home state.

“We have a long history of organizing a committee charged with thoroughly vetting applicants from the Oregon legal community,” the senators wrote. “We do not intend to return our blue slips for Ryan Bounds or any other nominee that has not been selected through our judicial selection process.”