A federal judge ruled against the Trump Administration's attempt to add a citizenship question to the 2020 Census.

Judge Jesse Furman of the U.S. District Court for Southern New York issued his decision on January 15, 2019, declaring the addition of the citizenship question to the census to be illegal.

The lawsuit was brought by a coalition of 18 states, the District of Columbia, 15 cities and counties, and the United States Conference of Mayors, as well as a variety of nonprofit groups. The question in the case was "whether Secretary Ross' decision" and the "process" leading to it, "violated provisions of statutory or constitutional law." Similar suits are also in progress in federal courts in Maryland and California.

Among the litany of problems identified by Judge Furman was the failure of the Commerce Department to follow Congress' clear policy preferences, "including but not limited to the preference for obtaining data through administrative records rather than through direct inquires." Overall, the Commerce Department "failed to consider several important aspects of the problem; alternately ignored, cherry-picked, or badly misconstrued the evidence in the record before him; acted irrationally both in light of that evidence and his own stated decisional criteria; and failed to justify significant departures from past policies and practices -- a veritable smorgasbord of classic, clear-cut" violations of the Administrative Procedures Act.

Furman's decision concluded that Commerce "Secretary Ross' decision to add a citizenship question to the 2020 census -- even if it did not violate the Constitution itself -- was unlwaful for a multitude of independent reasons and must be set aside. To conclude otherwise and let Secretary Ross' decision stand would undermine" the rule of law "with respect to what Congress itself has described as 'one of the most critical constitutional functions our Federal Government performs.' "

So, Judge Furman vacated the citizenship question's addition and enjoined the Commerce Department (and Census Bureau) from implementing it "or from adding a question to the 2020 census questionnaire without curing the legal defects."

As reported in ResearchLive:

The ruling was welcomed by research industry organisation the Insights Association. Howard Fienberg, vice-president of advocacy, said: "The decision is a win: stopping the asking of a question on citizenship in the decennial that hadn’t been properly tested and that was likely to reduce response rates (and thus accuracy) in immigrant communities (both legal and illegal) and in some native American communities."

Fienberg added: "The decision will presumably be appealed, but in the meantime, the Insights Association continues to urge congress to force the issue sooner, taking the question off the table for this decennial."