Minnesota intends to join other states in a planned legal challenge to the inclusion of a question about citizenship on the 2020 census.

A spokesman for Minnesota Attorney General Lori Swanson said Thursday that the state would be one of more than a dozen involved in the lawsuit involving the once-per-decade census. The lawsuit has not yet been filed, and Swanson’s office released no further details about its plans.

The U.S. Department of Commerce announced Monday that it would reinstate in the 2020 census a question about citizenship status that has not been used for decades. The agency said the question will help the U.S. Justice Department protect minority rights, but critics contend that it will lower census participation even among legal immigrants and cause the population to be undercounted.

California Attorney General Xavier Becerra filed a lawsuit Tuesday seeking to block the question from being included. The planned lawsuit by Swanson and other attorneys general apparently will proceed separately from that effort.

Also Thursday, Eric Holder, who was attorney general under President Barack Obama, told the New York Times that he will file a lawsuit seeking to block the census change. Holder, who now leads the National Democratic Redistricting Committee, said that past tweets by President Donald Trump will be used in the lawsuit to show that the aim of the citizenship question is not to protect voting rights.

“This is one of those incidences where I think the president’s tweets and public statements will become relevant,” Holder said.

Swanson, a DFLer, has previously allied with fellow Democratic attorneys general around the country in lawsuits aiming to block Trump administration orders and initiatives.

A group of 21 DFL members of the Minnesota House issued a letter Thursday that praised Swanson’s decision to make Minnesota part of the legal resistance to the census move, calling it “a statement about the basic human rights that Minnesotans value, uphold and celebrate.”

Several DFLers in Congress, including Minnesota’s Sen. Tina Smith and Rep. Betty McCollum, have sponsored legislation to bar a citizenship question from the census. But Republicans, who control Congress, have shown no support for those efforts.

The 2020 census has big political implications for Minnesota, which is one of a few states that could end up losing a congressional seat because population growth here has been slower than in some other parts of the country.