Supreme Court Poised to Rule on ‘Election Day’ Mail-In Ballot Case
A closely watched case now before the U.S. Supreme Court could have major implications for election administration across the country, including in California and more than a dozen other states that continue counting certain mail ballots after Election Day.
The case, Watson v. Republican National Committee, centers on whether federal law permits states to count ballots that arrive after Election Day if they were mailed on or before Election Day.
The justices heard oral arguments in March and are expected to issue a decision before the end of the Court’s current term this month.
At issue is a Mississippi law that allows absentee ballots to be counted if they are postmarked by Election Day and received within five business days afterward.
Republican challengers argue that the law conflicts with federal statutes establishing a uniform national Election Day for presidential, U.S. Senate, and U.S. House elections.
Their position is straightforward: federal law sets a single Election Day, meaning ballots must be received by then to be counted.
Mississippi officials argue that states retain broad authority over election administration and that ballots cast by Election Day should still be valid if they arrive shortly afterward.
The dispute began after Mississippi enacted House Bill 1521 in 2020 during the COVID-19 pandemic. The law created a five-day grace period for absentee ballots arriving after Election Day.
In 2024, the Republican National Committee and other plaintiffs challenged the law in federal court.
While a federal district court initially upheld Mississippi’s policy, the U.S. Court of Appeals for the Fifth Circuit later ruled that federal election law preempts the state’s post-Election Day ballot receipt window.
Mississippi appealed to the Supreme Court, which agreed to hear the case last year.
The stakes extend far beyond Mississippi.
According to election law data, roughly 15 states and the District of Columbia currently allow at least some ballots to arrive after Election Day and still be counted, provided they meet postmark requirements.
That includes California, where mail ballots can be counted if they are postmarked by Election Day and received within the state’s statutory deadline of seven days afterward.
A ruling for the challengers could force states to require receipt of ballots by Election Day for all federal elections.
Supporters of that approach argue it would create a clearer and more uniform national standard while reducing prolonged ballot-counting periods that can leave election outcomes unresolved for days or even weeks.
Critics argue that such a ruling could disenfranchise voters who mail ballots on time but experience postal delays outside their control.
During oral arguments, several justices appeared focused on the meaning of federal statutes establishing a single national Election Day. Court observers noted significant questioning about whether votes received after Election Day are consistent with Congress’s decision to establish one uniform federal election date.
No decision has been issued yet, and it remains unclear how the Court will ultimately rule.
However, the outcome could become one of the most consequential election-law decisions in years.
A ruling for the challengers would likely require states to revise ballot-receipt deadlines for federal elections and could substantially reduce post-Election Day vote counting nationwide.
A ruling for Mississippi would preserve existing state flexibility and allow current ballot-receipt grace periods to remain in place.
With the 2026 midterm elections approaching, election officials, political parties, and voting-rights organizations across the country are closely watching the case.
The Court’s decision is expected before the end of June and could establish a nationwide standard governing when ballots must be received in federal elections for years to come.
While the legal dispute began in Mississippi, the Supreme Court’s ruling could have implications far beyond one state’s election laws.
Currently, a significant number of states permit some form of post-Election Day ballot receipt period. Under these systems, ballots are counted as long as they were mailed by Election Day and arrive within a specified number of days afterward.
Nearly 150,000 California Mail Ballots Rejected In Primary
California election officials are examining why nearly 150,000 mail-in ballots were rejected during the state’s June primary, with late-arriving ballots accounting for most of the increase.
The higher rejection rate comes despite years of election law changes designed to make voting more accessible and ensure more ballots are ultimately counted.
According to data compiled by the California Secretary of State’s office, 148,241 mail-in ballots were rejected during the June primary, representing 1.73% of all mail ballots returned.
That marks an increase from the 2024 primary, when 108,982 ballots were rejected, or 1.56% of all mail ballots cast.
The largest reason for rejection was ballots arriving too late to qualify under California law.
State data shows that 93,479 ballots were rejected because they failed to meet the state’s deadline requirements.
California allows mail ballots to arrive up to seven days after Election Day, provided they are postmarked on or before Election Day.
Voting experts believe many of the rejected ballots received postmarks dated after Election Day, making them ineligible to be counted even if they arrived within the seven-day grace period.
Kim Alexander, president of the nonpartisan California Voter Foundation, said the timing of postal processing appears to be a significant concern.
“Ballots rejected due to lateness are caused primarily to being postmarked too late to count, not because they arrived too late to count,” Alexander said.
Election experts have questioned whether recent operational changes within the U.S. Postal Service may be contributing to delayed postmarks.
Earlier this year, a group of mostly Democratic U.S. senators wrote to the Postal Service expressing concern that mail-processing changes could affect ballot handling during federal elections.
Updated Postal Service procedures mean postmarks may reflect when mail is processed at regional facilities rather than when it first enters the mail system.
Because processing centers have been consolidated in some areas, election officials have warned that postmark timing could be affected.
Before the June primary, California election officials encouraged voters to mail ballots as early as possible because of potential postal delays.
The June election also featured a highly competitive race for governor, which some experts believe encouraged many voters to wait until the final days before casting ballots.
In addition to late-arriving ballots, approximately 44,000 ballots were rejected because election officials determined the voter’s signature did not match the signature on file.
Another 8,300 ballots were rejected because the return envelope did not contain a signature.
State records also show that 743 ballots were rejected because those voters had already cast another ballot.
Other rejected ballots involved missing ballots inside return envelopes or multiple ballots submitted in a single envelope.
The highest rejection rate in the state occurred in Tulare County, where 3.52% of returned mail ballots were rejected.
Alpine County and Merced County followed closely, each recording rejection rates of 3.36%.
California has frequently faced criticism for taking weeks to complete vote counting after major elections, largely because state law permits ballots meeting certain requirements to continue arriving after Election Day.
Following the June primary, President Donald Trump again criticized California’s election system, while the Department of Justice opened an investigation into election administration in Los Angeles County.
Election experts emphasize that the increase in rejected ballots should not be interpreted as evidence of widespread voter fraud.
A 2025 report by the Brookings Institution found documented cases of mail ballot fraud remained extremely rare, estimating roughly four cases for every 10 million mail ballots cast, The Associated Press reported.
State officials have not identified evidence of widespread fraud connected to the June primary, but the increase in rejected ballots is expected to receive additional scrutiny as election administrators evaluate whether changes in postal operations, voter behavior or election procedures contributed to the higher rejection rate.
