WASHINGTON — The Supreme Court on Wednesday allowed Rep. Mike Bost’s lawsuit challenging his home state of Illinois’ mail-in ballot policy to move forward, issuing an opinion that could have major implications for future elections.
In a 7–2 decision, the high court determined that Bost (R-Ill.) and the two Illinois primary delegates for President Trump,who joined his suit, have standing to sue despite lower courts concluding that they hadn’t provided evidence of harm.
“Candidates have a concrete and particularized interest in the rules that govern the counting of votes in their elections, regardless of whether those rules harm their electoral prospects or increase the cost of their campaigns,” Chief Justice John Roberts wrote for the majority.
“Their interest extends to the integrity of the election—and the democratic process by which they earn or lose the support of the people they seek to represent.”
Roberts was joined by conservative Justices Samuel Alito, Clarence Thomas, Neil Gorsuch and Brett Kavanaugh.
The sixth conservative Justice, Amy Coney Barrett, filed a concurring opinion backed by liberal Justice Elena Kagan.
Liberal Justices Ketanji Brown Jackson wrote a dissent backed by Justice Sonia Sotomayor.
Bost and his fellow plaintiffs are challenging Illinois law allowing mail-in ballots postmarked before Election Day to be counted up to two weeks after polls close.
They filed the suit against the Illinois State Board of Elections in 2022.
Complicating their effort to sue the state is the fact that it’s difficult to prove harm before votes have actually been cast, which is why the lower courts found they lacked standing.
Bost, who is pursuing a seventh term in the House during the 2026 midterm elections, was reelected with 74.2% of the vote and has never won an election by fewer than six percentage points.
At least 17 states, as well as Washington, DC, permit mail-in ballots that were postmarked by Election Day to be tabulated for a certain period of time after voting ends, according to the National Conference of State Legislatures.
“Under Article III of the Constitution, plaintiffs must have a ‘personal stake’ in a case to have standing to sue,” Roberts added. “Congressman Bost has an obvious answer: He is a candidate for office. And a candidate has a personal stake in the rules that govern the counting of votes in his election.”
Barrett, backed by Kagan, split with the majority’s logic for why Bost had standing to sue.
“Congressman Bost has standing because he has suffered a traditional pocketbook injury, not because of his status as a candidate,” she wrote. “…Rather than take this straightforward path, the Court charts a novel one: To challenge ‘the rules that govern the counting of votes in his election,’ a candidate need only allege that he is in fact a candidate in that election.”
In his majority opinion, Roberts countered that under Barrett’s approach “a candidate who pays poll watchers a penny would have standing,” while “one who relies on volunteers would not.”
“Nothing about Article III requires this result.”
Jackson chided in her dissent that Barrett’s “pocketbook theory would allow political candidates to spend their way past Article III’s injury-in-fact requirement” and argued broadly that “political candidates can and should be held to the same actual-injury requirements as other litigants.”
During oral arguments in October for Bost v. Illinois Bd. of Elections, the high court had signaled it was inclined to allow Bost’s case to move forward.
Its decision now seemingly opens the floodgates for a slew of pre-election lawsuits challenging procedures to move forward, which could have consequences for the 2026 midterms, 2028 presidential election, and beyond.
Notably, Trump and his allies had filed over five dozen lawsuits in the aftermath of the 2020 election.
Almost all of them were stopped from moving forward on the basis of standing, for various reasons.
