For decades, the Senate has employed a traditional practice that grants outsized influence to the input of individual senators concerning the president's judicial and prosecutorial nominees from their home state.

Known as the "blue slip," President Donald Trump has repeatedly railed against this practice and urged Republican leadership in the Senate to abolish or ignore it, as he just did again this week, according to The Hill.

Trump's problem with the blue slip practice is that it has been effectively wielded by Democratic senators to essentially block from consideration any of the president's preferred nominees for district judge and U.S. attorney positions.

Trump rants against Senate's "blue slip" tradition

On Thursday, President Trump once again expressed his displeasure with the Senate's blue slip tradition, as he wrote in a Truth Social post, "I have eight GREAT U.S. Attorneys, Highly Respected ALL, who will not be confirmed for their positions in various Highly Consequential States only because they’re Republicans."

"And the Democrats have convinced Chuck Grassley to honor the stupid and outdated 'Blue Slip' tradition, which precludes very talented and dedicated people from attaining High Office," he continued in reference to the Republican chairman of the Senate Judiciary Committee. "The Democrats violate this practice in order to get people in, but Republicans just don’t."

"These GREAT people’s careers have been badly hurt by the Radical Left Democrats, using an old and ridiculous custom strictly to their advantage. What a shame!" Trump added.

The president wasn't finished there, though, as he further lamented in a follow-up post, "A 'Blue Slip' means that if you’re a Republican President, and there happens to be just one Democrat Senator in a state where you are appointing a U.S. Attorney or District Court Judge, you will never be successful in getting a Republican confirmed."

"In other words, 'Blue Slips' are a disaster, and I have eight GREAT Republican U.S. Attorney Candidates who will not be able to fulfill their service to the people of a state that voted overwhelmingly for me," he added. "The only one I can appoint is a Democrat, and that’s not the deal. Nobody can say that is fair or, even, Constitutional."

Trump's right to make appointments "taken away" by Senate Dems

As President Trump noted, Senate Democrats have effectively used the blue slips as a partisan veto against Trump's nominees from their home state, and Senate Republicans have largely deferred to the objections of their Democratic colleagues and refused to move forward on nominees that don't receive the full approval of both senators from their home state, regardless of party.

This also isn't the first time that Trump has vented against the tradition, as he did so in August, according to a separate report from The Hill, in such a way as to elicit a response from Sen. Chuck Grassley (R-IA).

"I have a Constitutional Right to appoint Judges and U.S. Attorneys, but that RIGHT has been completely taken away from me in States that have just one Democrat United States Senator," Trump posted at that time. "This is because of an old and outdated 'custom' known as a BLUE SLIP, that Senator Chuck Grassley, of the Great State of Iowa, refuses to overturn, even though the Democrats, including Crooked Joe Biden (Twice!), have done so on numerous occasions."

"Therefore, the only candidates that I can get confirmed for these most important positions are, believe it or not, Democrats!" he added. "Chuck Grassley should allow strong Republican candidates to ascend to these very vital and powerful roles, and tell the Democrats, as they often tell us, to go to HELL!"

Grassley has defended the blue slip practice

The Hill reported that Sen. Grassley responded to that late-August post from the president by explaining that nominees who lacked a blue slip typically also lacked sufficient votes to be cleared by the committee or confirmed in a floor vote, and that in his role as chairman, he was focused on setting up Trump's nominees for "success" and not "failure."

"Chairman Grassley has already successfully moved U.S. Attorneys through committee who have received blue slips from Democrats, including Senators Warner and Kaine of Virginia and Klobuchar and Smith of Minnesota," a spokesperson for the senator told the outlet. "When a nominee comes out of committee, all 100 senators have a say on the nomination, and part of their consideration is based on the home state senators’ input."