Dek: A federal judge rejected the Justice Department’s bid to isolate more than 20,000 California mail ballots allegedly tied to noncitizens, but the litigation is not over.
The most consequential live 2026 election-administration case is unfolding in California, where the Justice Department is trying to force officials to isolate mail ballots linked to more than 20,000 people the federal government says are “likely” noncitizens. The case asks whether federal officials can interrupt a state’s established ballot-processing system shortly before Election Day based on a federal data-matching list.
On October 28, U.S. District Judge David O. Carter denied the department’s request for a temporary restraining order. The ruling leaves California’s ordinary procedures in place for now, but the Justice Department has said it is appealing and will seek emergency relief from the U.S. Court of Appeals for the Ninth Circuit. 1
What the Justice Department is asking for
Fact: The United States sued California and the Los Angeles County registrar on October 15. The complaint says the Department of Homeland Security and Justice Department compared California voter-registration records with federal and third-party information and identified more than 20,000 registered voters who were “likely” noncitizens. 3
The federal government asked the court to stop officials from tabulating mail ballots returned by people on that list until their citizenship could be verified. It also sought an order requiring California to review the names and set aside ballots when citizenship could not be confirmed. The government’s legal theory is that California’s treatment of the voters conflicts with the federal prohibition on noncitizens voting in federal elections, 18 U.S.C. § 611. 3
The department has not established, in the materials described by the court, how many people on the list actually returned ballots. A list of suspected ineligible registrants is not the same as a count of ballots cast unlawfully.
Why the Ninth Circuit did not intervene first
The Justice Department initially tried to obtain emergency relief from the Ninth Circuit before Judge Carter ruled. On October 26, a divided panel dismissed that appeal for lack of jurisdiction and denied the emergency motion as moot. 4
The appellate court said the government had appealed after the district court had not ruled within roughly 15 hours of an expedited request. But the district judge had already scheduled a hearing for October 27 and said he would rule promptly. The Ninth Circuit concluded that the government had not shown the extreme urgency that can turn judicial inaction into a constructive denial of emergency relief. 4
Fact: The panel also emphasized timing. The government had raised concerns about California’s voter rolls by July 16, while California’s laws allowing mail ballots to be issued to registered voters and processed before Election Day were longstanding. The complaint was filed October 15, after counties could begin processing ballots. 4
Analysis: The timing issue is important beyond this case. Courts often hesitate to change election procedures close to voting deadlines because late orders can confuse voters, burden administrators and make errors difficult to correct. The Supreme Court’s “Purcell principle,” named for Purcell v. Gonzalez, is the main legal backdrop, although its application and scope remain contested.
Why Judge Carter rejected ballot segregation
Judge Carter’s October 28 order rejected the TRO on several grounds. First, he found the government had not presented a sufficiently reliable basis for treating the entire October list as “highly likely” noncitizens. The order said the government did not disclose its specific matching rules, confidence thresholds, error rates or validation against a reliable benchmark. It also said the government did not adequately explain how an earlier estimate of nearly 200,000 alleged noncitizens became a list of more than 20,000. 5
The judge pointed to the government’s experience in Nevada as a warning about false positives. According to the order, DHS initially identified as many as 15,903 registered voters there as noncitizens, later reduced the number to 6,218 and then to 185 after manual review. Nevada officials later confirmed that all 185 were citizens. 5
That comparison did not decide whether any individual in California voted unlawfully. It affected whether the proposed mass remedy was justified before the election.
Second, the judge found that the requested process would impose major administrative costs. Los Angeles County’s system had no existing function for setting aside ballots belonging to designated voters. Creating a new process would require changes to software and hardware, new documentation and staff training while election officials were also preparing vote centers and handling rising mail-ballot volumes. 5
Third, the court viewed “temporary” segregation as potentially equivalent to disenfranchisement. The order said the government had not supplied a workable verification process that could confirm citizenship before Election Day. If a ballot were set aside without a timely way to clear it, the practical result could be that an eligible citizen’s vote was not counted. The judge specifically noted the risk to naturalized citizens, who can be wrongly flagged when databases do not match cleanly. 5
What the ruling does—and does not—mean
Fact: The ruling does not establish that noncitizens voted in California, nor does it permanently resolve the Justice Department’s claims. It denies emergency relief at the preliminary stage. California remains subject to federal and state laws barring noncitizens from voting in federal elections, and the government can pursue individual criminal cases where it has evidence. Judge Carter noted that California also has procedures to cancel registrations proven ineligible. 5
The decision also does not prevent later litigation over voter-list maintenance, federal-state election authority or the government’s data practices. It does mean that, at this stage, the court would not impose a new ballot-segregation system across an election already underway on the evidence presented.
Analysis: The case’s broader stakes concern who controls the operational details of voting. The federal government argues that states cannot knowingly facilitate illegal voting. California argues that a federal list based on undisclosed or unreliable matching cannot displace state safeguards or justify withholding ballots from registered voters. The court has so far placed greater weight on individualized proof, established procedures and the risk of disenfranchisement.
What to watch next
The immediate question is whether the Ninth Circuit grants the Justice Department’s promised emergency application after the district court’s final TRO ruling. The government has argued that every ballot processed without segregation risks diluting eligible citizens’ votes. California is likely to defend the existing process and the district court’s findings on reliability, administrative burden and late-stage election disruption. 2
The appellate court could deny emergency relief, allow the case to proceed on a fuller record or issue a narrower order. Any ruling may clarify how federal statutes interact with state ballot-processing rules and what evidence is required before action against many voters.
For now, California’s mail ballots will continue under the established system unless a higher court intervenes. The unresolved questions—how the list was built, whether listed voters cast ballots, and what remedy is lawful if illegal voting is proved—remain central to the case.
