U.S. District Judge Jesse M. Furman said he disagreed with government lawyers' claims that the legal "hurdle is exceptionally high" because Ross is a member of President Donald Trump's cabinet but he said even if a high standard did apply, he'd reach the same conclusion.
Furman said the deposition, which will be limited to four hours, was necessary "because Secretary Ross was personally and directly involved in the decision, and the unusual process leading to it, to an unusual degree."
The judge said a deposition was also necessary because government lawyers and Ross himself "have placed the credibility of Secretary Ross squarely at issue in these cases."
"There is something surprising, if not unsettling, about defendants' aggressive efforts to shield Secretary Ross from having to answer questions about his conduct in adding the citizenship question to the census questionnaire," Furman said.
The ruling came in response to two lawsuits by plaintiffs including over a dozen states and big cities who maintain Ross acted improperly. They claim the citizenship question will discourage immigrants from participating, diluting political representation and federal dollars for states that tend to vote Democratic.
The judge noted that Ross claimed in March when the decision to add the citizenship question was announced that he considered adding it after a request to do so last December from the Justice Department.
"The record developed thus far, however, casts grave doubt on those claims," the judge wrote.
Furman said Ross has admitted he began considering whether to add a citizenship question shortly after his appointment in February 2017 and consulted with various other government officials before demanding to know as early as May 2017 why no action had been taken on his request.
The judge said Ross has testified under oath that he was unaware of discussions between him and anyone in the White Houses over the citizenship question.
"But there is now reason to believe that Steve Bannon, then a senior adviser in the White House, was among the 'other government officials' whom Secretary Ross consulted about the citizenship question," Furman said.
"In short, it is indisputable - and in other (perhaps less guarded) moments, defendants themselves have not disputed - that the intent and credibility of Secretary Ross himself are not merely relevant, but central, to plaintiffs claims in this case," he said.
The judge also said aggressive efforts to shield Ross from answering questions were "surprising, if not unsettling."
Furman says it wasn't a close call as to whether Ross must be deposed. He said the public interest weighs heavily in favor of requiring Ross to answer questions.
Kate Bailey, a Justice Department lawyer, has said the government will immediately appeal any requirement that Ross answer questions.
A Justice Department spokesman declined comment Friday.
Amy Spitalnick, a spokeswoman for New York Attorney General Barbara D. Underwood, said: "We look forward to getting to the bottom of this as we continue our suit to ensure a full and fair Census."
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