On July 21, 2026, New Jersey Governor Mikie Sherrill announced that about 6,600 noncitizens had been accidentally registered to vote because of a software problem at the state's Motor Vehicle Commission. The news quickly became part of a bigger political fight, because the Trump administration has been arguing that large numbers of noncitizens are voting in U.S. elections. Fewer than 400 of those 6,600 people actually cast ballots, according to The Guardian.

Here is how the error happened. Since 2018, New Jersey has used an "automatic voter registration" system. This means that when someone visits a motor vehicle office for any reason, they are signed up to vote unless they specifically say no. Between 2023 and 2024, the computer software run by a company called IDEMIA failed to flag people who had indicated they were not U.S. citizens. Those people were then automatically added to the voter rolls, the official lists of who is allowed to vote. Sherrill said she learned about the error during the week of July 13. The governor and IDEMIA are now blaming each other for the mistake, with the company saying New Jersey approved the registrations, according to the New York Post.

The 6,600 people mistakenly registered are a tiny slice of New Jersey's more than 6.6 million registered voters. The ballots possibly cast from the error amount to about 0.009% of all ballots cast in the state's 2024 general election. Sherrill noted that both Democrats and Republicans were affected, with most not belonging to any party. Stephen Richer, a Republican who oversaw elections in Maricopa County, Arizona, from 2021 to 2025, said the incident is not an example of widespread voter fraud and pointed out that most of those mistakenly registered did not vote. David Becker, head of the Center for Election Innovation and Research, called the number a minuscule fraction of active registered voters.

Those calm assessments did not stop a strong political reaction. Donald Trump and his allies used Sherrill's announcement to push their claims about noncitizen voting. The incident came after Trump's July 16 primetime address, in which he stated: "According to the DHS review, state voter rolls and public records, they identified approximately 278,000 non-citizens who are registered to vote," and further claimed that "Hundreds of thousands of non-citizens and dead people are listed and active on the voter rolls," according to the transcript published by Roll Call's Factbase. The four states Trump's administration has pointed to for large numbers of noncitizens on voter rolls are California, Nevada, New Jersey, and Pennsylvania. DHS Secretary Markwayne Mullin claimed on or around July 17 that the agency had found 250,000 noncitizens registered across those four states.

A Guardian review of the letters DHS sent to states found the agency was less certain about the numbers than Trump's speech suggested, and gave no explanation of how it arrived at its figures. FactCheck.org published a detailed fact-check of the July 16 speech, and Deutsche Welle separately examined the revived election fraud claims. On Truth Social, Trump claimed that "35,152 is the new number just released by Homeland Security of non-citizens registered to vote in New Jersey," a figure that matches neither the 6,600 announced by Sherrill nor the 278,000 from his primetime address. The shifting, inconsistent numbers have been a defining feature of the administration's messaging.

The federal pressure on states began before the New Jersey disclosure. The Guardian reported on July 8 that the Trump administration had threatened states with criminal prosecution over demands for voter data tied to unproven noncitizen voting claims, and that state officials called the demands "truly bizarre behavior." Now the DOJ is moving from threats to possible action. Harmeet Dhillon, head of the DOJ's civil rights division, sent a letter to Governor Sherrill requesting the names of those who were registered and voted. The department is reportedly considering prosecutions related to the New Jersey incident, according to Politico.

The New Jersey error is real, documented, and being fixed. What makes it politically powerful is timing: it surfaced days after a presidential address built around claims that independent fact-checkers have not confirmed, and it is the first concrete, state-confirmed case of noncitizens appearing on voter rolls in a state the administration has targeted. But the scale is far below what the administration's language describes. The gap between the verified 6,600 registrations, fewer than 400 of which led to ballots cast, and the 278,000 figure Trump cited nationally is where the political fight is happening. Whether the DOJ pursues prosecutions, and on what legal basis, will determine whether this stays a narrow administrative fix or becomes a lasting part of the administration's election integrity agenda.