President Joe Biden and key Democrats have come out against a once broadly bipartisan bill that would create 63 new permanent judgeships now that President-elect Donald Trump would be the one to fill 22 of them.

The White House said Tuesday that Biden would veto the bill – passed unanimously by the Senate this summer and set for a House vote this week – that would add judgeships to the most overburdened federal courthouses in the country.

Judges across the ideological spectrum have warned that staffing shortages have created a major backlog in cases. The apparent collapse in support of legislation that would address the judicial shortfall shows how polarized the political environment around the judiciary has become has become, and how any measure that would expand the already-large imprint that Trump has made on the courts is deemed toxic to Democrats.

The bill’s Senate champions and outside supporters had hoped that the House would take up the bill before the election, when neither party would know which side would initially benefit from its passage. Democrats are now pointing to House GOP leadership’s failure to do so as reason why they’re reversing their support.

“Under this legislation, we all promised to give the next three unknown presidents a certain number of judges,” New York Rep. Jerry Nadler, the top Democrat on the Judiciary Committee, said at a House hearing on the bill Monday. “Because no one can tell the future we were all at an equal disadvantage, but for this deal to work, the bill had to be passed before Election Day.”

House Republicans have said they would have taken up the bill regardless of who won last month, and that they were unable to vote on it before the election because work needed to be done for it and because of the must-pass legislation that was before Congress before the election as well.

Rep. Darrell Issa, the California Republican who spearheaded the legislation, said Tuesday that the legislation was a “durable solution to a national judge shortage” and was the product of the “the work of a national array of stakeholders over a number of years,” ultimately earning “the support of a unanimous Senate and a strong bipartisan majority in the House.”

“The Biden White House can veto this bill, but it can’t stop a consensus idea whose time has come,” he said in a statement to CNN.

Judges – including in interviews with CNN – have said that the judiciary faces a staffing crisis that is undermining litigants’ right to speedy justice. The bill’s architects used the recommendations of the Judicial Conference, the policymaking body of the judiciary, to decide which courthouses would get additional judges – all for trial courts – under the bill, the “Judicial Understaffing Delays Getting Emergencies Solved Act” or JUDGES Act.

Fix the Court, a judicial transparency organization that is often on the opposing side of Republicans on issues concerning court ethics, is calling on the Biden White House to reverse its opposition, with its executive director Gabe Roth calling the veto threat “a slap in the face to our overworked federal judges.”

However, the left-leaning judicial advocacy Alliance for Justice praised Biden’s veto threat, arguing that “Every chance to protect our courts over the next four years must be taken.”

The Judicial Conference undertook a meticulous analysis to come up with its recommendations, while the bill’s authors used the feedback from lawmakers to craft the staggered, 10-year roll out of the additional judges, so to cover three different presidential terms and five Congresses. In some of the overburdened courthouses targeted by the legislation, the median criminal case can take years to resolve.

Still, the White House , while also acknowledging the post-election timing of the House vote, claimed in its announcement that the judges were being “hastily” added and that they were “unnecessary to the efficient and effective administration of justice.”

Senate Minority Leader Mitch McConnell said in a speech shortly before the White House’s announcement that it was “almost inconceivable that a lame-duck president could consider vetoing such an obviously prudential step for any reason other than selfish spite.”

“Litigants across America deserve their day in court,” McConnell said. “And they deserve to know the federal judiciary has the bandwidth to carefully and thoroughly consider their cases.”

McConnell has led Republican efforts in the past to block Democratic nominees for existing court vacancies, including the blockade of President Barack Obama’s 2016 Supreme Court nominee, Merrick Garland. The White House’s announcement on Tuesday noted that some of the new openings the JUDGES Act would create were in states “where senators have sought to hold open existing judicial vacancies.”

“Those efforts to hold open vacancies suggest that concerns about judicial economy and caseload are not the true motivating force behind passage of this bill now,” the White House said.

Lawmakers may try to get the bill passed in the new Congress, but getting Democratic support may require delaying the first allocation of new judges until 2029, when White House control will be unknown.