A federal judge has struck down the Trump administration’s decision to add a question about citizenship to the 2020 census.

Judge Jesse M. Furman of the Southern District of New York found that Commerce Secretary Wilbur Ross violated federal law by misleading the public — and his own department — about the reasons for adding the question, which would have forced everyone taking the census to answer whether or not they and others in their household are US citizens.

The census is supposed to be a count of everyone living in the United States — including noncitizens and even unauthorized immigrants — and the government is constitutionally required to use its count to make decisions about how many seats in Congress and electoral votes each state gets. The lawsuit over the citizenship question was filed by a coalition of blue states (led by New York) worried that asking about citizenship would discourage noncitizens from responding. A skewed undercount would understate the population of diverse states and deprive them of representation.

The Trump administration claimed it needed better citizenship data to enforce the Voting Rights Act and that the Department of Justice had asked Ross to add a citizenship question to the census for this reason. But emails and records uncovered as part of the lawsuit showed that Ross had been asking his staffers and other agencies to find reasons to add a citizenship question months before he received a letter from DOJ.

Furman also declared that Ross’s decision violated the federal Administrative Procedure Act, which governs how federal agencies make regulations and other decisions. Ross had ignored and in some cases lied about evidence from his own officials that found asking people about citizenship would decrease participation and increase cost. The ruling also finds that Ross and the Department of Commerce violated two specific provisions in the federal Census Act — one that seeks to limit the number of questions people are asked directly in the census and one regarding reports to Congress as the census is being planned.

The ruling doesn’t find that Ross acted unconstitutionally by adding the question, or that his intent was to discriminate against noncitizens or anyone else. That’s because Ross himself wasn’t questioned in the lawsuit. (The Supreme Court was scheduled to hear oral arguments on February 19 about whether Ross could be compelled to testify, but that question is now moot.)

Furman’s ruling will almost certainly be appealed. But the Trump administration will probably have to persuade the Supreme Court to step in on its behalf — either by issuing an emergency stay of Furman’s ruling or by agreeing to skip some steps in the legal process and take up the appeal — if it wants to include the citizenship question in the census questionnaires going to press later this year.

But the danger of a skewed census hasn’t gone away. The Trump administration is still allowed to include the citizenship question in its other census preparations. It’s planning to send a test census questionnaire (including the citizenship question) to 480,000 households in June.

The threat of adding a citizenship question — on top of general fears of government officials among immigrants in the age of Trump — might have been intimidating enough. It’s possible the damage has already been done.

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The lawsuit turned up plenty of evidence that asking about citizenship would cause problems — and that Ross ignored them

No one is disputing that the Trump administration has the authority to add questions to the census. What was at issue was the way the Trump administration went about making the decision.

The records that were exposed in this case made it clear that Ross and the Commerce Department hadn’t been telling the public the whole truth about that process.

Unlike most of the defeats Trump has suffered in court, which have started as preliminary rulings that seek to stop a policy while a court case is ongoing, this ruling comes after a full trial and the disclosure of lots of internal Department of Commerce records. So it’s able to go into much more detail about how decisions were made.

Furman’s ruling is not about the constitutionality of the citizenship question. Without testimony from Ross himself, Furman didn’t rule on whether Ross was motivated by “animus” in his decisionmaking. Instead, the case against the census question rests on the Administrative Procedure Act, which sets out how agencies are supposed to make policy that isn’t “arbitrary and capricious.”

Officially, the request to add a citizenship question to the census came from the Department of Justice in December 2017. But emails uncovered in the lawsuit showed that for months Ross himself had already been asking around about adding a citizenship question — and Commerce Department officials had tried to get other agencies involved to “clear certain legal thresholds.”

The Trump administration’s lawyers aren’t arguing that this was legal — indeed, they conceded that if the addition of the citizenship question was based on a pretext, it should be struck down.

Furman’s 277-page ruling also includes extensive findings of fact that Ross was warned about potential downsides of adding a new question — most notably, concerns that it would warp the census results by discouraging noncitizens from responding — and that he either ignored that evidence or claimed it didn’t exist.

In addition to the violations of the Administrative Procedure Act, though, Furman also found two specific violations of the Census Act, which is more specific in governing what the Commerce Department can do in developing the census in particular.

For one thing, the Census Act prohibits the government from asking people directly about information that the government could get just as easily from other records. Furman rejected the administration’s arguments that its other records weren’t good enough to figure out how many people in a given area were US citizens (not least because he pointed out that, since fewer people would participate in the census if a citizenship question were asked, the government would end up having to use other information to fill in the gap).

Additionally, Ross’s department didn’t include citizenship in its 2017 report to Congress about what topics the 2020 census would address — violating (according to Furman) a Census Act requirement that all topics be sent to Congress three years out, and that any change after that point be accompanied with a report about why the change was necessary.

The case will be appealed — but the clock is ticking

Furman’s ruling does not stop the administration from continuing to include the citizenship question in its 2020 census preparations, such as this summer’s test. But it does prohibit printing census questionnaires in which the citizenship question appears. (Technically, the Commerce Department could start the whole process over again and make a new decision to include a citizenship question, but given what came out in this trial, it’s not clear how it would do that without violating the law all over again.) And that printing will need to start this fall.

Typically, getting a case from the initial court decision to a Supreme Court appeal is a matter of years, not months. If the Trump administration is going to get the conservative Supreme Court to stop Furman’s ruling, it will need to get it to act more quickly than usual.

The administration could ask for an emergency stay to block Furman’s ruling from going into effect. (First, they’d have to ask the Second Circuit Court of Appeals for the stay; if the Second Circuit declined to give it to them, which it probably would, they could appeal to the Supreme Court.)

Without that, though, it’s going to have to either force the Second Circuit to hear the appeal on a very fast timeline, or get the Supreme Court to agree to take up the case even before the Second Circuit issues its own ruling — a move that the administration has tried before and that even this court hasn’t been willing to make.

So Furman’s ruling does make it substantially less likely that the 2020 census will include a citizenship question.

But the concern about participation in the 2020 census wasn’t just about the citizenship question.

Immigrant communities’ fear of public officials predates the Trump administration but has been kicked into high gear under this president. Trump has endorsed the idea that anyone living in the US without papers should fear deportation while the executive branch has aggressively scrutinized legal immigrants as well. Census officials were deeply concerned about immigrants’ participation in the 2020 census even when they weren’t asking about citizenship. Testers reported that respondents would walk out of their own homes rather than complete the in-person interview.

Advocacy groups and local governments are already trying to plan to encourage census participation even among people who have reason to fear Trump. It’s an uphill battle. And news stories about what the administration might do tend to persist as rumors in immigrant communities even when the administration isn’t actually doing it.

Furman’s ruling states as a “finding of fact” that asking about citizenship on the census will damage the integrity of its results by making many people in America afraid that participating will put them at risk. But that might be true already, whether the citizenship question ends up being printed on census forms or not.