The U.S. Court of Appeals for the Fourth Circuit on Thursday revived the NAACP's lawsuit alleging the U.S. Census Bureau's inadequate preparations for the upcoming 2020 census will lead to an undercount of minority populations.

The three-judge panel found in its opinion that it agreed with a district court ruling dismissing claims brought under the Administrative Procedure Act. But it ruled that the claims raised under the Constitution's enumeration clause could proceed.

The panel ordered that the case be remanded and the plaintiffs be allowed to file an amended complaint focusing on the enumeration clause claims.

Judge Barbara Keenan wrote in the majority opinion that the panel disagreed with U.S. District Judge Paul Grimm's finding that those allegations were not yet "ripe" at the time of its consideration.

Keenan wrote that the U.S. Supreme Court has previously held that plaintiffs have a right to challenge census procedures before the survey is conducted, "because such a pause would result in extreme—possibly irremediable— hardship."

"The injuries that the plaintiffs assert in this case arise from procedures that the defendants intend to use, or not use, in conducting the Census. Thus, the hardship that the plaintiffs would experience from the delay in adjudicating these claims is well established," she said.

In a concurring opinion, Chief Judge Roger Gregory wrote: "The foundation of representative democracy, then, rests in large measure upon Congress' faithful and meaningful compliance with the Constitution's mandate to count all persons in the nation."

"That there has been a historical undercount does not obviate Congress' constitutional mandate. Indeed, it magnifies that responsibility," he said.

The NAACP, Prince George's County of Maryland, the Prince George's County branch of the NAACP and two local residents first filed the suit in 2017 against the Census Bureau, Commerce Secretary Wilbur Ross, the acting director of the bureau and President Donald Trump.

Attorneys for Jenner & Block joined NAACP lawyers and the Yale Law School's Rule of Law Clinic in defending the plaintiffs.

The 2020 census has been the subject of intensive litigation, largely over the Trump administration's attempts to add a question on citizenship to the decennial survey. The administration withdrew that plan after the Supreme Court found the reasoning behind the question's inclusion was "contrived."

The Justice Department has agreed to pay more than $9 million in attorneys fees in four different cases over the citizenship question. Some of those funds are going to Big Law firms, including Covington & Burling, Arnold & Porter and Manatt, Phelps & Phillips.

Read more: