Here's the opening part of the piece. There's more discussion on the legal issues in the whole article.
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After an unprecedented move by the Trump administration to add a controversial question late in the Census planning process, courts will be asked to take an unprecedented step of preventing the administration from making the change before the count.
California filed a lawsuit challenging Commerce Secretary Wilbur Ross’ decision to add a citizenship question to the upcoming Census just hours after the change was announced. Several other groups and parties are lining up behind California Attorney General Xavier Becerra with plans to bring legal challenges of their own.
Every Census is the target of a fair share of lawsuits. But the legal ground to be tread this time will be fresh, Census experts and voting rights attorneys tell TPM.
“There is no clear analogous previous case, but there’s no clear previous analogous circumstance like this either,” said Thomas Saenz, president and general counsel of Mexican American Legal Defense and Educational Fund.
The stakes are extremely high, not just for immigrant populations, but for the states where they live and for the communities that serve them. If the question dis-incentivizes certain populations from participating — as many experts and advocates expect — the undercount would lead to a shrinking of their political representation, and a stiffing of federal resources allocated for them.
The lawsuit that California filed Monday alleges that the move violates the Constitution’s Enumeration Clause, which mandates that “actual enumeration” of people in the United State be used to apportion congressional districts. The suit also claims the addition of the question violates the Administrative Procedure Act, which prohibits “arbitrary and capricious” agency action.
“If you undertake methods, like the citizenship question, that are guaranteed to prevent you from conducting a Census that is fair and accurate, you are in dereliction of your basic constitutional duties,” said Tom Wolf, counsel with the Democracy Program at the Brennan Center, explaining the constitutional argument against adding the question.