Demonstrators gather at the Supreme Court last month. The court ruled the Trump administration had provided a “contrived” reason for wanting a citizenship question on the 2020 Census. (J. Scott Applewhite/AP)

The legal battle over the Trump administration’s efforts to put a citizenship question on the 2020 Census further escalated on Monday as the plaintiffs argued that Justice Department attorneys should not be allowed to withdraw from the case because they have not given “satisfactory reasons” for seeking to do so.

The Trump administration has not demonstrated that the withdrawals “will not cause further disruption, particularly in light of the history of this case and the well-documented need for expeditious resolution,” attorneys for those challenging the citizenship question said in a court filing in New York.

The filing comes in response to a request from the Justice Department attorneys on the case to withdraw.

The department had telegraphed the move a day earlier — saying it was replacing the team of career and political employees who had been handling the matter. A person familiar with the matter previously told The Washington Post that at least some of the career attorneys were frustrated with the handling of the case after President Trump ordered the department to explore more options for adding the citizenship question to the 2020 Census after the lawyers, seeing no other possibilities, had conceded defeat.

In asking to withdraw the attorneys from the case, the department argued that it did not expect the move would cause a “disruption.” But those suing said the department should articulate more clear reasons for the attorneys’ attempted withdrawal, arguing that government lawyers had previously made “rapidly shifting representations” to the court.

They also requested the judge “require any attorneys whose representations or conduct is at issue in the pending or forthcoming motions to attend any hearings on these motions or otherwise remain available to the Court and the parties to ensure the full and fair disposition of the pending motions.”

If the judge inquires further, the matter could cause more heartburn for the Justice Department as it is forced to detail in court more of its internal business.

Challengers in the case include Democratic-led states and civil rights and immigrant rights organizations. They have argued that the citizenship question would result in an undercount of millions of people who fear acknowledging that a noncitizen is part of their household.

In a ruling late last month, the Supreme Court blocked the Trump administration’s plan, saying the government had provided a “contrived” reason for wanting the citizenship information.

The Justice and Commerce departments then effectively conceded defeat — but Trump soon ordered the lawyers to do an about-face and come up with ways to keep the fight alive.

On Monday, Attorney General William P. Barr told reporters in South Carolina that he has been in “constant discussions” with Trump ever since the ruling and that the administration is “considering all the options.” He sounded optimistic about the chances that the citizenship question will appear on the 2020 Census, although he declined to provide details of the administration’s next steps.

“I think over the next day or two, you’ll see what approach we’re taking, and I think it does provide a pathway for getting the question on the census,” Barr said.

In an interview with the New York Times, Barr maintained that Trump was “right on the legal grounds” and said he “can understand” if the original Justice Department lawyers are “interested in not participating in this phase.”

Robert Barnes contributed to this report.