A new memo released by a U.S. congressional committee this week confirmed that a longtime Republican redistricting specialist was directly involved in efforts by the Trump administration to add a citizenship question to the 2020 U.S. Census, a new court filing in New York federal said.

Attorneys for the New York Immigration Coalition wrote in the filing that evidence released this week by the U.S. House Oversight Committee corroborated that claim, first made in May.

"Defendants have had countless opportunities to be straight with Plaintiffs and this Court," they wrote. "Instead, they have repeatedly misled and have never provided a complete record."

The NYIC is represented by attorneys from the American Civil Liberties Union, the New York Civil Liberties Union, and law firm Arnold & Porter Kaye Scholer.

It's the latest filing in the group's lawsuit against the Trump administration over its attempt to add a question about citizenship to next year's census. The New York Attorney General's Office is also involved in the litigation, but wasn't included in the new filing.

The U.S. Supreme Court blocked efforts to add the citizenship question to the census in a decision handed down earlier this year in the litigation.

Since that decision, attorneys for the NYIC have been asking a federal judge to impose sanctions on the U.S. Department of Justice after at least two witnesses from the federal government either withheld documents or allegedly provided misleading testimony.

The new evidence revealed by Congress this week showed that officials previously deposed in the litigation provided false or misleading testimony, attorneys wrote, and failed to produce relevant communications during discovery, including emails and text messages.

Those documents show that a close adviser to U.S. Commerce Secretary Wilbur Ross sought approval from the redistricting specialist on language that was included verbatim in an early draft of a letter that formally requested the citizenship question.

That redistricting specialist, Dr. Thomas Hofeller, has since died. But the new court filing, for the first time, showed an email exchange he had with an official tied to the question.

"Defendants sought to brush off evidence of Hofeller's role in adding a citizenship question to the census as a 'conspiracy theory,' but the newly-released documents confirm that Hofeller played an even bigger part in Defendants' scheme than previously was understood," attorneys for the NYIC wrote.

The email from Hofeller was sent to A. Mark Neuman, an adviser to Ross and former member of Trump's transition team. Neuman, in a previous email, had sent Hofeller a body of text that appeared to support a question about citizenship on the next census.

The subject line of the email from Neuman to Hofeller was the word "Census," according to the filing. It was sent in late August 2017—four months before the citizenship question was formally requested by the U.S. Department of Justice to be added to the census.

"Please make certain that this language is correct," Neuman wrote. "Dale doesn't return my calls."

Neuman was referring to Dale Oldham, who was Hofeller's business partner. Hofeller replied to Neuman that Dale had read the text sent in the email and that it was "fine as written."

The text sent for review by Neuman was an argument that current census data wasn't adequate for purposes of redistricting. Two recent court cases, the text said, supported that finding: LULAC v. Perry and Bartlet v. Simpson.

"We wanted the Bureau to be aware that two recent Court cases have underscored that ACS data is not viable and/or sufficient for purposes of redistricting," the text in the email said.

That email exchange was never disclosed, despite Neuman being deposed as part of the litigation last year and an extensive discovery process that included several instances where the Trump administration was ordered to hand over documents that it initially wanted to withhold.

About five weeks after that email exchange, the same body of text popped up again—but this time in a text message sent by Neuman to John Gore, a senior DOJ official.

It's not the first time Gore's been involved in the litigation. He was central to the case last year after he was found to be the individual who ghostwrote a letter from the DOJ to the Commerce Department formally requesting that the citizenship question be added.

That letter wasn't signed by Gore; it appeared, at the time, to be authored by Arthur Gary, general counsel of the Justice Management Division at the DOJ.

At least one earlier draft of that letter was disclosed to attorneys for the NYIC last year as part of the lawsuit. But one, included in the text message exchange between Neuman and Gore, had not been provided at any point of the litigation.

"This version of the DOJ request letter, which Neuman sent to Gore, was not produced, logged, or otherwise disclosed," attorneys for the NYIC wrote.

Neuman texted the entire draft to Gore in October 2017, two months before the Gary letter was sent. That draft included language verbatim to the body of text that Neuman sent to Hofeller for approval about a month earlier.

"We wanted the Bureau to be aware that two recent Court cases have underscored that ACS data is not viable and/or sufficient for purposes of redistricting," the text message said.

Neuman later met with Gore about the draft included in the text message, according to the memo from Congress. Neuman then provided a "readout of his meeting" with Gore to Peter Davidson, general counsel at the Commerce Department. Davidson then briefed Ross.

"[Ross] appreciated the update and your help," Davidson later texted to Neuman.

That text message also wasn't disclosed as part of the lawsuit last year, according to the filing. Withholding that exchange, and others, was unlawful, attorneys for the NYIC wrote.

"Another thing is now obvious: Neuman produced documents and communications to congressional investigators that were highly relevant to this case but somehow went undisclosed in litigation," the filing said.

"At all points in discovery, through many twists and turns, Neuman and Defendants withheld these documents from Plaintiffs and the Court," it continued.

The new evidence, they wrote, should be enough for U.S. District Judge Jesse Furman of the Southern District of New York to impose sanctions on the Trump administration.

Attorneys for the NYIC are seeking additional discovery in the litigation to determine what kind of sanctions they'll seek from the court. They're asking Furman to force the Trump administration to disclose certain documents that were initially labeled as privileged last year.

The connection between Hofeller and the citizenship question, which was first alleged in May, has been called "the product of a conspiracy theorist" by the Trump administration in previous filings. They've said Hofeller wasn't involved in drafting the letter written by Gore.

Representatives from the DOJ and the Commerce Department did not immediately respond to a request for comment on the filing Friday.

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