WASHINGTON — A group spearheaded by former US Attorney General Eric Holder is suing the Trump administration in an attempt to block its plans to add a last-minute citizenship question to the 2020 Census.
The federal lawsuit, which was to be filed Wednesday on behalf of seven residents of Maryland and Arizona, contends the question is at odds with the constitutional requirement that the census count every person residing in the United States, including noncitizens.
Commerce Secretary Wilbur Ross announced the addition of the question last month, triggering an outcry from immigrant advocacy groups and Democratic lawmakers, who stand to lose political power if undocumented immigrants and their families refuse to respond to the survey.
‘‘Coming amidst what the Bureau itself has identified as a widespread climate of fear among citizen and noncitizen immigrants, the belated addition of a citizenship question will significantly depress response rates in certain communities, thereby undermining the completeness and the accuracy of the 2020 census,’’ the lawsuit states. Holder’s group planned to file it in federal court in Maryland.
The lawsuit makes a similar argument to other actions brought in recent weeks by an array of states and localities, but it is the first to be filed on behalf of individual residents who, the suit says, will be adversely affected.
‘‘This lawsuit is a direct challenge from affected individuals,’’ said Holder, who chairs the National Democratic Redistricting Committee, which is seeking to help Democrats across the country as congressional lines are redrawn, a process informed by census results.
The lawsuit is being coordinated by the National Redistricting Foundation, a nonprofit organization affiliated with the committee Holder chairs.
Holder, who served as attorney general under then-President Barack Obama, said residents of Maryland and Arizona were selected to underscore that the citizenship question has negative consequences on those living in states with different political leanings.
‘‘Blue states as well as red states are impacted by this,’’ Holder said.
He said residents from other states might be added to the lawsuit later.
Officials in Arizona have declined to join other lawsuits challenging the Trump administration. Maryland is among the plaintiffs in a separate suit that includes 17 states and the District of Columbia.
Census tallies are used to determine representation and distribution of resources, including the number of seats in the US House, number of electoral college votes, and apportionment of hundreds of billions of federal dollars.
Ross has argued that data from a citizenship question could help identify potential voting-rights violations by providing more accurate information than currently available about the proportion of a congressional district’s population that is eligible to vote by virtue of holding citizenship. Citizenship information currently comes from a survey that samples a small percentage of the population.
Holder dismissed that argument, saying the current process is sufficient.
