A software glitch in New Jersey mistakenly registered thousands of non-citizens to vote, allowing nearly 400 to cast ballots, Governor Mikie Sherrill has said.

The disclosure has reignited debate over election integrity in the US. In a statement on Tuesday, the White House argued the incident underscored the need to pass President Donald Trump’s SAVE America Act, which would require states to verify citizenship before registering voters in federal elections. Democrats and voting rights advocates, however, said the case reflected an isolated administrative error rather than evidence of widespread non-citizen voting.

According to Sherrill, the glitch affected roughly 6,600 people applying for driver’s licenses or identification cards through the state’s Motor Vehicle Commission between mid-2023 and mid-2024. Although they correctly identified themselves as non-US citizens, a software malfunction automatically added them to the voter rolls.

State officials said fewer than 400 of those mistakenly registered ultimately voted. The ballots accounted for less than 0.01% of the more than four million votes cast in New Jersey during the 2024 election, and the authorities said they found no evidence that the error affected the outcome of any race.

Sherrill said the problem came to light only recently. Her administration has ordered an investigation, directed election officials to remove all ineligible registrations, and said the software contractor responsible for the faulty system will be replaced.

The governor also criticized the previous state administration, accusing it of failing to detect and disclose the problem sooner.

Federal officials have urged states to review their voter registration databases, while election authorities in several states have questioned broader claims of non-citizen voting and called on Washington to provide evidence supporting them.