The Census Bureau plans to use the survey with a citizenship question in its 2030 test, worrying experts

ORLANDO, Fla. (AP) — The U.S. Census Bureau plans to use a survey form with a citizenship question as part of a practice test for the 2030 Census, raising questions about whether the Trump administration might try to make a major change to the once-a-decade headcount that failed during the president’s first term.

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The field test, conducted in Huntsville, Alabama, and Spartanburg, South Carolina, uses questions from the American Community Survey, the comprehensive survey of American life, rather than questions from recent census forms.

Among the questions posed to the ACS is: “Is this person a US citizen?” Census questions are not supposed to be about citizenship, and haven’t been for 75 years.

Last August, Trump instructed the Commerce Department to have the Census Bureau begin working on a new census procedure that would exclude immigrants who are in the United States illegally from the census.

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The Fourteenth Amendment to the Constitution provides that “the aggregate number of persons in each State” shall be calculated in relation to the numbers used for apportionment, the process of apportioning congressional seats, and the electoral college votes among the states. The Census Bureau has interpreted this to mean anyone living in the United States, regardless of their legal status.

The office did not respond Thursday to inquiries seeking comment about why ACS questions were used in the 2026 exam.

ACS questions have never been used in a census field test before, said Terri Ann Lowenthal, a former congressional staffer who advises on census issues. She said the 2026 test — reduced from six sites to two — became “a wrapper of what the Census Bureau has proposed and what needs to be done to ensure the accuracy of the 2030 Census.”

“This complete shift from real field testing is troubling and deserves immediate congressional attention, in my view,” Lowenthal said.

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The field test gives the Census agency the opportunity to learn how to better count populations that were undercounted during the last census in 2020 and improve methods that will be used in 2030. Among the new methods being tested is using US Postal Service workers to do tasks previously done by census workers.

Testing was originally supposed to take place in six places, but the Trump administration announced earlier this week that it had removed four sites — Colorado Springs, Colorado, western North Carolina, western Texas and tribal lands in Arizona.

Mark Mather, associate vice president at the Population Reference Bureau, a nonpartisan research group, said he could not speculate on the political motivations behind the decision to use the ACS questions, but said the more fundamental concern was methodological.

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“The ACS model will not provide a valid test for the 2030 Census processes,” he said. “It’s a completely different animal.”

In his first term, President Donald Trump tried unsuccessfully to add a citizenship question to the 2020 Census form. He also signed orders that would have excluded people in the United States illegally from allocation numbers and mandated the collection of citizenship data.

The US Supreme Court blocked the attempt to add a citizenship question, and both orders were canceled when Democratic President Joe Biden arrived at the White House in January 2021, before the 2020 census numbers were published.

Republican lawmakers in Congress recently introduced legislation that would exclude some noncitizens from allocation numbers. Several GOP state attorneys have also filed federal lawsuits in Louisiana and Missouri seeking to add a citizenship question to the upcoming census and exclude people who are in the United States illegally from the apportionment count.