President Donald Trump on Thursday said he has directed the U.S. Department of Commerce to begin work on a “new and highly accurate” national census that would exclude undocumented immigrants from the population count. In a post on his Truth Social platform, Trump wrote that the tally should be based on “modern-day facts and figures” and draw on information from the 2024 presidential election, adding that “people who are in our Country illegally WILL NOT BE COUNTED.” The order revives a push Trump undertook during his first term, when his administration attempted to add a citizenship question to the 2020 census and later sought to remove undocumented migrants from the figures used to allocate House seats. Both efforts were blocked by federal courts, and President Joe Biden rescinded the policy in 2021. Census data determine the apportionment of congressional seats and guide the distribution of hundreds of billions of dollars in federal aid. Excluding an estimated 11 million undocumented residents, according to a 2022 Homeland Security estimate, could shift political representation and funding among states. Constitutional experts expect legal challenges, noting that Article I, Section 2 requires a count of “the whole number of persons” in each state. The next decennial census is scheduled for 2030.