The Justice Department’s lawsuit follows a demand that California review a list of 20,000 names within 48 hours. The department says those people were sent ballots; California mails ballots to all registered voters. The lawsuit asks a judge to require local officials to set aside ballots for anyone whose citizenship cannot be independently verified.

California Secretary of State Shirley Weber rejected the demand, saying the federal government had not provided evidence or explained the methods used to identify the people on the list. She said voting is already underway and called the request an unprecedented threat to eligible voters’ rights.

Weber also pointed to a recent Nevada case in which federal officials flagged nearly 16,000 people as possible noncitizens on voter rolls, but the state found they were U.S. citizens. In a letter to the Justice Department, she described the latest demands as an “emergency of the DOJ’s creation.”

The delivery of the list has also raised security concerns. Los Angeles County Registrar Dean Logan said his office received a password-protected thumb drive this week, with the password written in a handwritten note. Weber’s office said the password was on a sticky note. Logan said he did not consider the device secure.

California Attorney General Rob Bonta said state officials would not comply with the request to withhold ballots. He noted that the administration’s figures had shifted: the Department of Homeland Security had claimed over the summer that 190,000 noncitizens were on California’s voter rolls, while the Justice Department’s current list names 20,000 people. “What happened to those 170,000? They just got those wrong,” Bonta said.

Bonta also argued that the federal government’s demand conflicts with a law barring states from making certain changes to voter rolls within 90 days of an election. The lawsuit characterizes the case as a routine request for election-related relief and accuses California of making no serious effort to identify noncitizens registered to vote.

The dispute comes as the administration has made identifying noncitizen voters a priority. Noncitizens are not eligible to vote in federal elections, but such voting is rare. The Justice Department has charged about 90 people this year with various forms of election misconduct, including 50 accused of voting as noncitizens. More than 227 million people were registered to vote nationally in the 2024 presidential election.

The lawsuit seeks a court order before ballots are tabulated. The competing claims leave California election officials facing a time-sensitive legal challenge as voting proceeds, while the state says the federal list is unsupported and could put eligible voters’ ballots at risk.