US Secretary of Commerce Wilbur Ross.
CNN  — 

A federal judge in New York on Thursday allowed a lawsuit against the Trump administration that threatens to block the addition of a citizenship question on the 2020 Census to proceed.

The decision came after US Federal Judge for the Southern District of New York Jesse Furman denied a motion filed by Trump administration officials to dismiss the suit.

“Granted, courts must give proper deference to the Secretary, but that does not mean that they lack authority to entertain claims like those pressed here,” Furman wrote in his decision. “To the contrary, courts have a critical role to play in reviewing the conduct of the political branches to ensure that the Census is conducted in a manner consistent with the Constitution and applicable law.”

The Commerce Department has said it is adding the citizenship question to the 2020 Census at the request of the Justice Department to improve enforcement of the Voting Rights Act.

Furman, however, warned that just because the case is allowed to go further does not mean the question will not appear on the Census.

“As noted, the Enumeration Clause and the Census Act grant [Commerce Secretary Wilbur Ross] broad authority over the Census, and Plaintiffs may not ultimately be able to prove that he exercised that authority in an unlawful manner,” Furman wrote.

New York Attorney General Barbara Underwood called the decision a “big win” in a statement.

“As we’ve argued, the Trump administration’s plan to demand citizenship status as part of the Census is unlawful – and it would potentially cause a huge undercount that would threaten billions in federal funds and New York’s fair representation in Congress and the Electoral College,” Underwood said in a statement.