(Daily Signal)—Although the Supreme Court issued a stinging defeat to President Donald Trump and Republicans in an election integrity case, justices have more such cases in the pipeline.
One solidly red state, Mississippi, and two battleground states, Arizona and Pennsylvania, were the focal point of election litigation on Monday. The high court ruled 5-4 to uphold a Mississippi law that allows for counting ballots arriving up to five days after Election Day, so long as the ballots are postmarked by Election Day.
The Republican National Committee was the plaintiff in the case, while the Trump Justice Department stated an interest in the case, backing the RNC’s side against the Mississippi law.
“In the RNC v Watson case, the Supreme Court lost a critical opportunity to interpret the meaning of Election Day and now the fight goes to the Congress and state legislatures,” former U.S. Election Assistance Commission Chairman Don Palmer, now a senior legal fellow at The Heritage Foundation, told the Daily Signal.
“Instead, the court has prolonged the delay and confusion Americans witness with late-arriving ballots. Unfortunately, the practice will continue in a minority of states and have a negative impact nationwide on the confidence in our elections. All states should implement legislation enacting Election Day as the deadline for the return of mail ballots.”
The ruling affects more than a dozen states and territories across the country that allow the counting of mail ballots arriving after Election Day.
Illinois and Utah count ballots arriving up to 14 days after Election Day, according to the National Conference of State Legislatures. Alaska and Maryland allow ballots postmarked by Election Day to be counted up to 10 days after the election.
California, the District of Columbia, New York, and Oregon count ballots arriving seven days after the election. New Jersey counts ballots arriving up to six days post-election, while West Virginia’s grace period is five days.
California was the subject of criticism after a recent primary election for Los Angeles mayor, where Republican Spencer Pratt appeared to be headed for the runoff on election night before he was edged out by Los Angeles City Council member Nithya Raman several days later, as more ballots came in.
Nevada and Ohio count ballots arriving up to four days after Election Day, while Kansas, Massachusetts, and Virginia count ballots arriving up to three days after Election Day. Washington state law says that ballots received after the election with postmarks before Election Day are counted, but no deadline is specified for when they must be received, according to the National Conference of State Legislatures.
Before releasing any decisions Monday morning, the high court announced that it would take up the case of Republican National Committee v. Mi Familia Vota.
The question before justices in that case is whether Arizona can require proof of citizenship for voter registration. The high court accepted an appeal from the RNC after lower courts determined portions of Arizona’s 2022 voting law violated the National Voter Registration Act of 1993, better known as the “motor voter” law.
Assistant U.S. Attorney General Harmeet Dhillon of the Civil Rights Division asserted on X that this is a “Very important case!”
“We @CivilRights briefed the importance of this case. Clean voter rolls are essential to election integrity and voter confidence,” Dhillon posted.
The court can “clarify whether states can request proof of citizenship of applicants as part of the eligibility review of voter registration and whether noncitizens erroneously placed on the voter rolls can be immediately removed within 90 days of a federal election,” Palmer said.
“Both of these questions, if answered approvingly, would give states the necessary information to increase the accuracy and integrity of our voter registration process. In the registration process, states often need documentation to verify citizenship status at the point of registration.”
The court will also decide if the state can remove the names of ineligible voters from the rolls within three months of an election, which plaintiffs say violates the “quiet period” of the federal voting registration law.
The Supreme Court is also deciding whether to hear a mail-in ballot case out of Pennsylvania and on Monday asked the Trump administration for its view in the matter.
At issue is a state law that requires envelopes to be sent with the ballots containing a signature and date. Liberal groups, including the Democratic Congressional Campaign Committee, sued, alleging the state law led to the discarding of 10,000 ballots in 2022 and of 4,500 ballots in 2024. Plaintiffs claim it violates the right to vote.
Pennsylvania Attorney General David Sunday, a Republican, appealed the case to the Supreme Court.
In August 2025, the 3rd U.S. Circuit Court of Appeals upheld a lower court ruling that enforcing ballot dates is not constitutional. The appeals court determined that the potential to discard thousands of votes is not a reasonable trade-off for the “unlikely capacity to detect and deter fraud.”
