Oregon Attorney General Ellen Rosenblum says a move to include a question about citizenship on the 2020 census could wreak financial havoc on Oregon. 

Rosenblum joined officials from 16 other states Tuesday in filing a lawsuit to block what they call an “unconstitutional and arbitrary decision” by the White House. 

“We are required to know who, where and how many residents live here,” Rosenblum said at a press conference in New York City, where she appeared next to New York Attorney General Eric Schneiderman. “Yet this question about citizenship discourages accuracy and inclusion and it runs counter to the intent behind the law, as inscribed in our Constitution.” 

The dispute arises from the Department of Commerce’s decision last month to ask about respondents’ citizenship on the upcoming census. The census has not asked all U.S. households about citizenship since 1950. 

Detractors like Rosenblum say the decision to revive the question contributes to an environment of fear spurred by recent crackdowns on undocumented immigrants. They worry the question could reduce response rates among Oregonians, leading to a costly undercount. 

“Many federal programs rely on the population figures collected in the decennial census to allocate federal funds among states and local governments,” the suit says. By asking about immigration status, it argues, the government might cause an undercount in states with large immigrant populations, “depriving them of their statutory fair share of federal funding.”

The lawsuit goes on to list federal funds Oregon received in 2015: $431 million for highways, $39 million for child care development, and $57 million in grants for urban transportation. 

Even a 1 percent undercount in the 2010 census would have resulted in a $23 million loss in federal funds, according to Rosenblum’s office.  

Plaintiffs are also concerned a miscount will affect the accuracy of Congressional districts, which are drawn based on population. 

Plaintiffs joining Oregon in the suit include Connecticut, New York, Delaware, Illinois, Iowa, Maryland and Minnesota. Six cities — Chicago, Seattle, New York, Philadelphia, Providence, Rhode Island and Washington, D.C. — are also signing on.

The federal suit, filed in New York’s southern district, asks a judge to declare the decision to add a citizenship question “unauthorized by and contrary to the Constitution and laws of the United States.”