President Trump used a primetime address earlier this month to again allege widespread noncitizen voting, warning that more than 250,000 migrants could be registered in four states. But the Department of Homeland Security has not provided a clear explanation of how it arrived at that figure, and correspondence reviewed by The Hill shows the agency itself found only 118,000 matches through a so-called preliminary review.
The letters sent to Pennsylvania, New Jersey, California and Nevada demand those states hand over their voter rolls, but all four have refused, citing state laws that bar sharing sensitive voter information with federal authorities. California Secretary of State Shirley Weber wrote to Homeland Security Secretary Markwayne Mullin late last week, expressing deep skepticism about the department's data and methods.
“I have serious doubts about the reliability of your data and accuracy of your claims, since my office has not shared our statewide voter registration list with DHS or any other federal agency or official,” Weber wrote in a letter obtained by The Hill. She noted that state law prohibits sharing voters' Social Security numbers and other personal data with the federal government, and added, “Your letter provides no detail whatsoever that my office can use to evaluate the veracity of your allegations.”
The DHS claimed it found names in its own databases that matched the birthday, address and Social Security number of individuals on state voter rolls. But since none of the four states have turned over their registration lists, it remains unclear how the department could have made such matches. All four states are currently in litigation to block federal access to their rolls, and Democratic-led states have won all 16 lawsuits filed so far to prevent such access.
Rep. Madeleine Dean (D-Pa.) dismissed the administration's numbers as “fuzzy math,” borrowing a phrase from former President George W. Bush. “How’d they get those numbers? How did they get those Social Security numbers? Because Al Schmidt responded and said, ‘We’re not giving you the voter rolls,’” she said, referring to Pennsylvania’s Republican secretary of state. “It’s misinformation, if not direct lies.”
Neither the White House nor the DHS responded to repeated inquiries from The Hill seeking details on their methodology. Instead, officials pointed to the initial press release, which contained the same top-line figures. Those numbers sharply diverge from independent studies by both left- and right-leaning organizations. The Brennan Center for Justice found just 30 instances of noncitizen voting out of 23.5 million votes reviewed in 2016. The Heritage Foundation, the group behind Project 2025, found only 24 cases nationwide between 2003 and 2023.
Stephen Richer, a legal fellow at the libertarian Cato Institute who studies election administration, warned of the dangers of relying on incomplete data matches. “The problem is using anything short of a last four [of someone’s Social Security number] plus date of birth or 10-digit driver’s license in this world of hundreds of millions of registered voters and imperfect data files — it just doesn’t have a high accuracy rate,” he said. Richer also questioned why the DHS didn’t provide states with individual records to verify the alleged matches. “If it was really about identifying if we have an issue and correcting that issue, it seems like you’d want to give the states the individual voter records that you’re alleging are bad,” he said.
In the letters, Mullin claimed high numbers of potential noncitizen registrants but only detailed how the DHS reached a fraction of those totals. For Pennsylvania, he wrote that as many as 14,576 noncitizens could be registered, but the DHS found only 8,594 matching names in its database. For New Jersey, the claim was 35,152, with 19,497 matches. The states each said they already conduct regular voter list maintenance, including checks for noncitizens, deceased individuals and people who have moved.
New Jersey Gov. Mikie Sherrill (D) acknowledged a recent error when DMV software accidentally registered about 6,600 drivers who disclosed they were not citizens. That incident underscores the complexity of such data matching, but it also shows that states can identify and correct problems without federal intervention. The Trump administration's push for access to state voter rolls comes as part of a broader effort to tighten election rules, including asking the Supreme Court to reinstate mail-in voting restrictions ahead of the midterms.
For now, the gap between the administration's sweeping allegations and the lack of verified evidence leaves election officials and experts skeptical. As Richer put it, “To just send them a list with a number on it, what are you supposed to do with that?”
