By Charles Lam

Asian-American community advocates are worried that the Census' proposed citizenship question could grow more politicized after the Supreme Court announced today that it will take up the battle over a citizenship question for the 2020 census.

As many as 18 states, several major cities and civil rights groups have sued the federal government over its decision to ask about citizenship in the next census, alleging that the question would make immigrants wary of responding and result in an undercount of the population.

“The inclusion of the citizenship question, we think, will have a devastating impact on our communities’ participation in the census. Asian American and Pacific Islander communities are already distrustful of the government,” said Dan Ichinose, director of the Demographic Research Project at Asian Americans Advancing Justice - Los Angeles. While his group is not a party to the lawsuit, a partner nonprofit is.

Census Bureau research published in January has found that non-Hispanic Asians were the least likely to say they planned to respond to the census and were most concerned that their answers were going to be used against them.

“Including the question will magnify community concern and increase the number of Asian Americans and Pacific Islanders who refuse to participate,” Ichinose said.

A federal judge previously ruled that while a citizenship question would be constitutional, Commerce Secretary Wilbur Ross had added it arbitrarily and that he had not followed proper administrative procedures.

An accurate census is important since it helps decide the number of seats awarded to states in the House of Representatives and how $675 billion a year in federal funds is distributed, which can go to projects such as studying why Native Hawaiians and Pacific Islandershave higher rates of diabetes and obesity than average.

“If we’re undercounted, that means we’re not getting the funding that we need to serve this population,” Nia Aitaoto, co-director of The Center for Pacific Islander Health at the University of Arkansas for Medical Sciences, told NBC News last year.

"It really does have considerable impact on our communities' political representation and the funds that come into our communities to address some very real concerns," Ichinose said.

Issues that advocates say could reduce the census response rate include the Census Bureau’s increased reliance on the internet in 2020, housing situations that may push respondents not to answer, and respondents’ fear that their answers could be used against them or in treaty negotiations between the United States and their home countries.

Last year, the Census Bureau told NBC News in an email that Title 13 of the U.S. Code “requires that responses to Census Bureau surveys and censuses be kept confidential and used for statistical purposes only.”

“Additionally, by law, the Census Bureau cannot publicly release any responses that could identify a survey respondent or share answers with law enforcement agencies,” the bureau said.

The Supreme Court said Friday that it plans to issue a decision by June after scheduled arguments in April.

In the meantime, Asian Americans Advancing Justice - Los Angeles is working to ensure respondents reply to the census. They expect to offer reference materials in about 20 languages, Ichinose said, and during the last census, trained approximately 80 groups and 3,000 individuals to perform census outreach.

“Obviously, we’re unequivocally against adding a citizenship question and our concern is the Supreme Court’s decision to take up the case will further politicize the issue,” he said. “We’re hopeful that they’ll see that the inclusion of the question really does compromise the government’s ability to follow its constitutional mandate to count all Americans.”

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