Trump's census plan could reshape voting maps, eliminate race questions

The Trump administration's renewed attempt to rewrite the rules for counting the U.S. population could upend congressional apportionment in future elections and likely spark a flurry of legal challenges.

Why it matters: The administration has proposed cutting undocumented immigrants and people without lawful permanent status from the 2030 tally, a sharp expansion of Trump's prior attempts to overhaul the count that could redefine who is considered part of the U.S. population.

• "The current administration wants to have their own definition of who are real Americans, which is not the same as what the census has counted for many, many decades," says William Frey, a senior fellow with Brookings Metro and a demographer who has been a consultant to the U.S. Census Bureau.

Driving the news: The Census Bureau's proposed rule posits that undocumented immigrants, among others, should no longer be included in the count because they are not "true inhabitants" or "persons with a 'usual residence'" in the U.S. because of a lack of "allegiance."

• "The scope of the proposed changes is breathtaking in how ... it'll affect census operations, census results, and equally important, public confidence in the integrity of the count," says Terri Ann Lowenthal, the former staff director of the House subcommittee that conducted census and federal statistical system oversight.

Catch up quick: Trump's first-term attempts to change census rules, including by adding a citizenship question, failed. But the new proposal also revives that charge.

• Trump announced last August that he had instructed the Commerce Department to "immediately begin work" on a new census excluding undocumented immigrants.
• Axios previously reported that the administration was moving forward with a field test as part of its early 2030 planning using the American Community Survey (ACS) form, which included a citizenship question.

By the numbers: While the exact impact on congressional apportionment is unclear at this point, Pew Research Center found in 2020 that if unauthorized immigrants were removed from the census apportionment count, three states — California, Florida and Texas — would've lost a House seat.

• "The administration is now trying to use the residence rules as a back door to influence the results of the census for political and partisan purposes," Lowenthal, also a Census Bureau policy consultant, contends.

Zoom out: The administration's proposal also floats removing questions about race and ethnicity from the census, as well as barring questions about sexual orientation. The census has collected race data since 1790.

• The proposal wouldn't stop demographic questions on the ACS, but Lowenthal tells Axios that the ACS isn't meant to count the population, while the decennial census provides the benchmark for all other samples.
• "Race and ethnicity data from the ACS is not fine-grained enough to support the monitoring and enforcement of civil rights laws, such as fair housing laws, equal educational opportunity [and] the Voting Rights Act," Lowenthal says.

Zoom in: Insights Association, the trade association for market research and data analytics, warned in a letter to Commerce Secretary Howard Lutnick that without "an authoritative, universal benchmark" of race and ethnicity data, "survey results cannot be reliably generalized to the public."

What we're watching: The proposal is sure to trigger legal challenges, with New York Attorney General Letitia James already signaling she's waiting in the wings.

• "We stopped the Trump administration's census attacks in 2020, and we're exploring our legal options to fight back again," she said in a Wednesday post.

Go deeper: Trump says he's ordering a new census. Here's what the Constitution says