The American Civil Liberties Union, the New York Civil Liberties Union and several advocacy organizations filed a lawsuit Wednesday challenging the Trump administration’s plan to add a citizenship question to the 2020 census.

The lawsuit charges that the question discriminates against immigrants and goes against the constitutional mandate to count all people living in the United States. Plaintiffs include CASA de Maryland, the American-Arab Anti-Discrimination Committee and the ADC Research Institute.

The lawsuit, which calls the question “a naked act of intentional discrimination directed at immigrant communities of color,” is the latest in a series of legal challenges from states, cities and civil rights organizations since Commerce Secretary Wilbur Ross announced in March that the question would be added. Along with Ross and the Commerce Department, also listed as defendants are the Census Bureau and its acting director, Ron Jarmin.

The Justice Department requested in December that the survey ask about citizenship, saying the information is needed to enforce the Voting Rights Act. But critics contend the question, which has not appeared on the decennial survey since 1950, is unnecessary and will depress response rates among immigrants leery of the government’s intentions.