Months after the end of the legal battle over the now-blocked citizenship question, the trail of emails and internal memos about the Trump administration's push to include the question on the 2020 census is getting longer.

In addition to a lawsuit the House Oversight and Reform Committee filed Tuesday over redacted documents, two recent surprising turns of events have resurfaced questions about whether administration officials are holding on to potential evidence of the citizenship question's true origins.

In a court filing released Monday, the Justice Department said that it recently realized 41 pages of emails and other documents from the files of a high-ranking Census Bureau official — Christa Jones — were "inadvertently" not shared with attorneys for the question's challengers when the lawsuits were still active.

"The fact that these documents may not have been produced only came to light last week when the Department of Commerce reviewed its files in response to Congressional requests for documents," DOJ attorney James Gilligan wrote in the filing.

The DOJ is "still investigating" whether any other documents were "similarly inadvertently omitted," Gilligan added.

That revelation came almost two weeks after previously undisclosed emails from 2017 confirmed that a then-adviser to the administration, Mark Neuman, had direct communication with Thomas Hofeller, a prominent GOP redistricting strategist who had concluded adding a citizenship question to census forms would be "advantageous to Republicans and Non-Hispanic Whites."

The emails were made public earlier this month by the House Oversight and Reform Committee, which had obtained them from Neuman as part of its ongoing congressional investigation into why the administration wanted the question. Neuman also turned over text messages he sent to Justice and Commerce officials.

On top of these developments, the federal lawsuit by the House oversight committee, led by Rep. Carolyn Maloney — a Democrat from New York — is the latest effort to force U.S. Attorney General William Barr and Commerce Secretary Wilbur Ross, who oversees the census, to release unredacted copies of previously released documents about the citizenship question.

The administration has claimed various privileges, including executive privilege, to fend off the committee's subpoenas.

In a written statement, Justice Department spokesperson Kerri Kupec derided the legal challenge as "nothing more than a political stunt."

Still, the administration continues to face allegations of withholding evidence and providing misleading or false testimony in sanctions proceedings requested by challengers of the citizenship question represented by the ACLU, New York Civil Liberties Union and the law firm Arnold & Porter.

U.S. District Judge Jesse Furman — the first federal judge to rule to block the question — is reviewing those allegations and may rule shortly.

In new sworn statements filed to Furman, former administration officials John Gore and Peter Davidson say that even after recently finding the text messages from Neuman on their personal cellphones, they don't remember reading them.

Gilligan, the DOJ attorney, conceded in another court filing that the Trump administration's document searches for the lawsuits "may not have been perfect" but added that the Federal Rules of Civil Procedure "do not require perfection."

"A party's search for documents responsive to an opponent's discovery requests must be reasonable and proportionate to the needs of the case," Gilligan wrote.

In their request for sanctions, opponents of the administration represented by the ACLU are calling for a "full accounting of what happened." They're asking Furman to consider unsealing certain redacted portions of already released internal documents and allowing additional questioning under oath of officials to "clarify" the role played by Hofeller, as well as Ross, Jones and other senior leaders.

"It's awfully convenient that they keep finding more and more documents," says Sarah Brannon, managing attorney for the ACLU's Voting Rights Project. "At some point, the court is going to have to put its foot down to address these repeated failures to comply with their discovery obligations."

While this fight over documents continues, the administration continues to move forward with its alternative to the citizenship question — compiling government records on citizenship to produce data that Hofeller said would politically benefit Republicans when voting districts are redrawn after the census.

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