Justices Appear Open to Challenge of Mail-In Ballot Rules by Illinois Politician

The Supreme Court will hear arguments on Wednesday in a case dealing with rules allowing mail-in ballots in Illinois to be counted even if received after Election Day, a practice permitted in many Democratic-led states that has been repeatedly challenged by Republicans.

At issue in the case is the narrow question of whether a federal elected official can sue to stop a state from counting such ballots.

Under Illinois law, ballots postmarked by Election Day are counted if they are received up to 14 days later.

Representative Mike Bost, a six-term Republican who represents a district in downstate Illinois, and two electors filed a lawsuit in May 2022 arguing that the late-ballot rule is superseded by laws enacted by Congress setting the time for federal elections.

The lawsuit was one of several challenges brought by allies of President Trump to question the guidelines around mail-in ballots, which he has long attacked and falsely blamed for his 2020 election loss as more people voted by mail during the pandemic.

It is also the first of several voting rights and election-related disputes the justices are scheduled to hear this term, setting up an important year for the court and the mechanics of democracy.

Although the question presented in Mr. Bost’s case is narrow, a victory for him could clear the way for other such challenges, including a Mississippi case pending before the court testing whether a five-day post-election grace period for late mail-in ballots violates federal law.

In July 2023, a federal judge dismissed the case, finding that Mr. Bost had failed to show he had standing to sue, a threshold legal requirement that Mr. Bost demonstrate he suffered a direct injury from the law.

Mr. Bost asserted that he had suffered a financial cost because he had to run his campaign for two weeks after the election to monitor ballot receipts and counting. He also argued that, as a candidate, he had a particular interest in an accurate tally of votes.

A divided panel of three judges on the U.S. Court of Appeals for the Seventh Circuit disagreed, finding that Mr. Bost was not required to conduct post-election monitoring. Any financial injury, the judges found, was self-inflicted.

Mr. Bost appealed to the Supreme Court, arguing that his case presented “an opportunity for the court to provide lower courts and litigants much-needed guidance on candidate standing, outside of the high-stakes, emergency, post-election litigation where these issues commonly arise.”

In his November 2024 petition asking the court to take the case, Mr. Bost argued that “the ability of candidates and parties to sue over state laws affecting their campaigns has been narrowed again, and, indeed, may never have been so restricted.”

He claimed that the lower courts had improperly dismissed the case by treating his likelihood of winning the election as relevant to whether he had standing, arguing that judges should not “try to predict electoral outcomes” but rather should focus on whether a state election law “inflicted real costs” on a campaign.

The justices announced in June that they would take up the matter on the narrow question of whether he could bring the legal challenge.

In a brief to the court, the Illinois attorney general, Kwame Raoul, argued that Mr. Bost had failed to demonstrate that he was injured by the state election law.

To bring a challenge to such laws, Mr. Raoul wrote, a political candidate “must demonstrate a concrete and particularized injury traceable to a challenged election rule, not merely voice objection to that rule.”

In response, lawyers for Mr. Bost argued that political candidates had “standing to challenge the rules that govern the time, place and manner of their elections” and that they had “a unique and concrete interest in the rules that govern the elections into which they pour enormous resources.”