New York Attorney General Barbara Underwood wants her lawsuit against the Trump administration over its decision to ask about citizenship on the 2020 U.S. Census to go to trial—but not only because her team thinks they have a better legal argument.

Lawyers with the Attorney General's Office said in a new filing late Thursday that deciding the lawsuit by trial, rather than summary judgment, would help uncover the Trump administration's motivations to add the question, which was announced by U.S. Commerce Secretary Wilbur Ross in March.

“This case presents serious factual questions as to the motivation of the secretary, the presence of improper political interference, and whether the secretary's ultimate decision was predetermined,” said the filing from Underwood's office, written by senior trial counsel Elena Goldstein.

U.S. District Judge Jesse Furman of the Southern District of New York has already scheduled a tentative trial date in the lawsuit for Nov. 5. After lawyers for the Trump administration pushed back on bringing the lawsuit to trial last week, Furman said he would accept a brief this week explaining why summary judgment is appropriate for the case. Underwood's office filed its reply brief late Thursday.

Underwood is leading a coalition of 18 state attorneys general in the lawsuit, which was filed in April shortly after the citizenship question was announced.

The attorneys general have argued that asking about citizenship will decrease turnout for the census in states with large immigrant populations, like New York. That could have a ripple effect by causing those states to lose representatives in Congress and the Electoral College. The attorneys general also argued that a smaller recorded population could mean less federal funding in areas like education and health care.

The lawsuit started—and continues to be—an effort by those states to block the Commerce Department from asking about citizenship on the census. The original complaint explained how the question could negatively impact states and municipalities with immigrant-dense communities.

But discovery over the past few months, and particularly in the last month, has shown a different side of the litigation. Furman said in July there was “strong” evidence the Trump administration acted in bad faith when deciding to add the citizenship question. That decision kicked off discovery in the case, which has produced documents and testimony the coalition hopes to use during trial to their advantage.

Underwood's office noted the July decision regarding bad faith in its filing Thursday to go after Ross.

“And the materials produced thus far in litigation have confirmed this view; the secretary radically altered long-established agency policy, disregarded the uniform opposition of his professional staff and outside experts, reached out to a separate and reluctant agency to manufacture a post hac rationale, and then repeatedly misrepresented his decision-making process to the public and to Congress,” the filing said.

Lawyers for the Trump administration disagreed in their filing with Furman this week. They said the decision on bad faith isn't enough to bring the case to trial.

The lawsuit alleges that Ross and the Commerce Department violated the Administrative Procedures Act because the federal government did not have data or a clear explanation for adding the citizenship question. Kate Bailey, the lead attorney on the case for the Trump administration, wrote in their filing this week that bringing the lawsuit to trial would go against precedent of deciding such claims by summary judgment.

“Deciding this case by bench trial, rather than cross-motions for summary judgment, not only distorts this court's defined role as a court of review rather than a finder of fact, it also risks improperly altering the focus of this court's review on the merits.” the DOJ's filing said. “Clearly, then, the APA claim in this case should be decided like every other APA claim: on cross-motions for summary judgment.”

Underwood's office addressed that argument in their filing, saying that courts have found it appropriate in the past to review APA claims by trial when there are allegations of bad faith or when there is competing expert testimony. This case has both.

What the case doesn't have, at least so far, is testimony proving where the idea to add the citizenship question came from and who was involved in the final decision.

That's why Underwood's office asked Furman earlier this month to compel the deposition of Ross. Other government officials deposed in the case have suggested that only Ross would know what led to the question being added. Furman has not decided on the deposition.

An email included in a different filing from the plaintiffs this week showed Ross had considered the citizenship question during the early months of the Trump administration—almost a year before it was announced.

“I am mystified why nothing [has] been done in response to my months old request that we include the citizenship question. Why not?” Ross wrote in an email dated May 2, 2017.

The DOJ has asked Furman to block the deposition of Ross, saying it would be extraordinary. They argued in a filing that testimony from high-ranking officials in the executive branch is usually not allowed to “safeguard the separation of powers.”

Besides, they said in a different filing, even if the court finds Ross wanted to add the citizenship question all along, that does not necessarily mean he acted in bad faith.

“Even if the court concludes that the secretary may have held a preexisting policy preference before making his decision and that he consulted with other agencies before making a final decision, that is not evidence of bad faith,” the filing said.

Underwood's office has, meanwhile, continued to close in on officials they believe to be at the center of the case. They asked Furman this week to compel the deposition of Mark Neuman, who previously chaired the Census Bureau's National Advisory Committee. Neuman was also on the transition team for the Commerce Department after Trump's election in 2016, but finished his service on the transition before Ross was confirmed.

According to testimony obtained through the deposition of Earl Comstock, a Commerce Department official, Neuman was an adviser on the citizenship question to Ross and others at the agency despite no longer working in government. 

Underwood is leading the lawsuit along with attorneys general from Connecticut, Delaware, Illinois, Iowa, Maryland, Massachusetts, Minnesota, New Jersey, New Mexico, North Carolina, Oregon, Pennsylvania, Rhode Island, Virginia, Vermont, Washington and the District of Columbia.

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