Updated at 11:25 p.m. ET

A special three-judge court in New York on Thursday blocked the Trump administration's efforts to make an unprecedented change to who is included in the census numbers that determine each state's share of seats in Congress.

The president, the court concluded, cannot leave unauthorized immigrants out of that specific count.

The decision comes after the July release of a memorandum by President Trump that directs Commerce Secretary Wilbur Ross, who oversees the U.S. Census Bureau, to provide Trump with information needed to exclude immigrants who are living in the United States without authorization from the apportionment count.

The panel of judges — including U.S. Circuit Judge Richard Wesley, Circuit Judge Peter Hall and District Judge Jesse Furman — noted the president does have some direction over the census and how the results of the count are used for reapportionment. But that authority, which is delegated from Congress, is limited.

A "tabulation of total population" is what the commerce secretary is directed to report to the president from the once-a-decade census, under Title 13 of the U.S. Code. According to Title 2, the president, in turn, is supposed to hand off to Congress "a statement showing the whole number of persons in each State."

Because Trump's memo "deviates" from that "statutory scheme," the judges declared it "an unlawful exercise of the authority granted to the President."

The panel ultimately issued a narrow ruling against the memo.

"Because the President exceeded the authority granted to him by Congress by statute, we need not, and do not, reach the overlapping, albeit distinct, question of whether the Presidential Memorandum constitutes a violation of the Constitution itself," the panel wrote in their opinion.

Their injunction against the administration permanently bans it from including any information about the number of unauthorized immigrants in each state in the commerce secretary's report to the president. The judges, however, are not stopping the administration from "continuing to study whether and how it would be feasible to calculate" those numbers to allow the secretary to comply with the memo "in a timely fashion" in case a higher court overturns their ruling.

Since the first U.S. census in 1790, the country's official once-a-decade population numbers used to reapportion seats in the House of Representatives have included both U.S. citizens and noncitizens, regardless of immigration status. Enacted after the Civil War, the 14th Amendment ended the counting of an enslaved person as "three fifths" of a free person by requiring the counting of the "whole number of persons in each state."

The president ultimately plays a limited role in reapportioning Congress. After the president hands off the latest numbers to Congress, the clerk of the House of Representatives is supposed to send to the governors a "certificate of the number of Representatives" each state receives, according to Title 2 of the U.S. Code.

The Justice Department, which is representing the administration in these two lawsuits based in Manhattan, declined to comment on the judge's ruling, DOJ spokesperson Mollie Timmons said in an email to NPR.
"This is a huge victory for voting rights and for immigrants' rights," said Dale Ho, the director of the ACLU's Voting Rights Project who helped represent a coalition of plaintiffs led by the New York Immigration Coalition in one of the lawsuits.

This legal fight in New York reassembled many of the same challengers and attorneys who were part of litigation over the administration's failed efforts to add the now-blocked citizenship question.

"President Trump's repeated attempts to hinder, impair, and prejudice an accurate census and the subsequent apportionment have failed once again," said New York State Attorney General Letitia James, whose office led a group of states, cities and counties in the other Manhattan-based lawsuit over Trump's memo.

Trump's memorandum has sparked eight legal challenges around the country. In addition to the two based in Manhattan, federal judges are hearing cases over the memo in Northern California, Washington, D.C., Massachusetts and Maryland, where an ongoing lawsuit about the administration's efforts to produce citizenship data was expanded last month with additional allegations about the memo.

Fearing the loss of a House seat after the 2020 census, the state of Alabama is leading an ongoing case that was filed in 2018 to try to force the Census Bureau not to include unauthorized immigrants in the apportionment count.

The memo's challengers have raised concerns that its introduction in late July, shortly before door-knocking efforts for the 2020 census were about to launch nationwide, has helped deter many households with immigrants from taking part in the count.

"We want to make sure that our community knows that they count and we will go to any means to make sure that their humanity is respected," said Cesar Espinosa, executive director of FIEL, a Houston-based immigrant advocacy group. "We want to make sure that we do not go back in time when humans are counted as a fraction of a person."

The ruling in New York may be appealed directly to the U.S. Supreme Court. Federal law allows decisions by a three-judge court — which are convened for lawsuits challenging the constitutionality of how congressional seats are reapportioned among the states — to skip review by an appeals court.

In addition to this legal fight over who counts for reapportioning House seats, the bureau is embroiled in lawsuits over the Trump administration's directive to shorten the 2020 census schedule — already disrupted by the coronavirus pandemic — to make sure the president receives the apportionment count by Dec. 31.

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