The Supreme Court is expected to rule as early as this week on whether states can count mail-in ballots received after Election Day, a decision that could dismantle the extended ballot-receipt windows used by California and over a dozen other states.
The case centers on Mississippi's law, which allows ballots to be counted if postmarked by Election Day and received within five days. Challengers, led by the Republican National Committee, argue this conflicts with federal law designating the first Tuesday after the first Monday in November as Election Day for federal offices.
During oral arguments in late March, the Court's conservative majority appeared skeptical of the grace period. A ruling against Mississippi could force California to end its practice of accepting mail ballots up to seven days after Election Day, a change that election experts say would create immediate administrative chaos.
“That could create a crunch for states like California and some of the other vote by mail states,” said Geoffrey Skelley, chief elections analyst at Decision Desk HQ. “It’s because the Supreme Court might say with immediate effect ‘you can’t do this anymore.’”
California adopted universal mail-in voting during the pandemic, sending ballots to all 23 million registered voters. State law requires ballots to be dropped at secure locations by 8 p.m. on Election Day or postmarked by that date and received by the following Tuesday. As of Monday, roughly 1.6 million mail ballots from the June 2 primaries remained unprocessed, according to the Secretary of State's office.
The slow count has drawn sharp criticism from President Trump and other Republicans, who have made unsubstantiated claims of fraud. In a Sunday interview on NBC's “Meet the Press,” Trump alleged cheating in California's elections without providing evidence. Similarly, Senator JD Vance recently cast doubt on Los Angeles’ mayoral primary, citing mail-in ballot irregularities.
Conservative groups, including Citizens United, argue that extended deadlines increase fraud risks. “The longer the period over which the election is conducted, the greater the opportunity for and risk of fraud,” they wrote in a February amicus brief. “Some states are determined to extend election day, both before and after, transforming a day into an election season.”
Opponents of restricting mail ballots warn it could disenfranchise military and overseas voters. Janessa Goldbeck, CEO of Voice Vet Foundation, told The Hill: “Military and overseas voters frequently can’t control when the postal service or the military mail systems deliver their ballots, and if ballots mailed on time are discarded simply because they arrive after election day, service members could lose their right to vote through no fault of their own.”
A February analysis by VoteBeat found that roughly 373,000 California ballots in the 2024 election arrived after Election Day with valid postmarks—about 2.3% of the total vote. The Court could apply the Purcell principle to avoid changing rules before November, or issue a ruling that creates split deadlines: ballots for state and local races might still be accepted, while those for federal contests would not count.
The decision will have immediate implications for California’s upcoming U.S. House races, though not for the recently decided governor's and Los Angeles mayor's contests, which are state and local. The state’s slow vote-counting process has already raised concerns about future elections, as California’s slow vote count risks chaos in future contests. Meanwhile, the state's political landscape continues to shift, with candidates embracing nuclear power, leaving environmental groups behind.
