In a narrow ruling, the court said in the case the Trump administration did not give reasons to add a citizenship question to next year’s census. The administration argued that the question was necessary to enforce the Voting Rights Act. The decision is seen as a stunning win for civil rights groups and advocates opposing the addition, believing that it would lead to an inaccurate count of the nation’s population.

Critics also say Trump’s camp wanted to reduce the number of people counted as minorities in democratic districts. Data from the 2020 census is used to allocate congressional seats and distributing billions of federal dollars to states and municipalities in the next decade.

The justices returned the issue back to the Department of Commerce, which oversees the census, to offer further explanation. The high court’s decision comes as the Commerce Department has a Sunday deadline to start printing 2020 census materials.

Meanwhile, an angry Trump tweeted Thursday that he will ask lawyers to seek ways to delay the census.

“Seems totally ridiculous that our government, and indeed Country, cannot ask a basic question of Citizenship in a very expensive, detailed and important Census, in this case for 2020,” Trump said. “I have asked the lawyers if they can delay the Census, no matter how long, until the United States Supreme Court is given additional information from which it can make a final and decisive decision on this very critical matter.

“Can anyone really believe that as a great Country, we are not able the ask whether or not someone is a Citizen,” the president asked rhetorically. “Only in America!”

Supreme Court Chief Justice John Roberts, a conservative, sided with the court’s liberal justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor, and Elana Kagan in blocking the citizenship question. Justices Clarence Thomas, Samuel Alito Jr., Neil Gorsuch, and Brett Kavanaugh dissented.

Roberts wrote in his opinion that “the decision to reinstate a citizenship question cannot be adequately explained in terms of the (Justice Department’s) request for improved citizenship data to better enforce the (Voting Rights Act).”

The chief justice also took aim at Commerce Secretary Wilbur Ross. Roberts said several points taken into consideration “reveal a significant mismatch” between the decision Ross made and “the rationale he provided.” The chief justice added that the commerce department intended to include a citizenship question about a week into Ross’ tenure “but it contains no hint that he was considering (voting rights) enforcement in connection with the project.”

Roberts also said that the Department of Justice wasn’t interested in the citizenship data until contacted by the Commerce Department.

“The materials presented before us indicate that Commerce went to great lengths to elicit the request from (the) DOJ (or any other willing agency),” he said. “And unlike a typical case in which an agency may have both stated and unstated reasons for a decision, here the VRA enforcement rationale—the sole stated reason—seems to have been contrived.

“We are presented, in other words, with an explanation for agency action that is incongruent with what the record reveals about the agency’s priorities and decision-making process.”

Furthermore, Roberts said the decision to add the citizenship question to the census wasn’t “substantively valid.”

The American Civil Liberties Union (ACLU) said in a pair of tweets Thursday that the ruling is “a victory” for immigrants and communities of color.

“The Trump administration’s attempt to politicize and manipulate this fundamental pillar of our democracy has failed. Our communities will be counted,” the organization said. “This ruling is a victory for immigrants and communities of color across America. It is a victory for democracy itself.

“Everyone MUST come together to make sure that the 2020 census counts every person.”

And, New York Attorney General Letitia James, whose office spearheaded the lawsuit before the high court tweeted Thursday that the census will remain a tool for delivering on the “government’s promise of fairness and equity.”

“Our democracy withstood this challenge, but make no mistake, many threats continue to lie ahead from the Trump Administration and we will not stop fighting,” she said. “Now more then ever, everyday people need us to stand firm in our fight for justice.”

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