The United States Supreme Court has reached a deadlock in a case over whether a religious charter school in Oklahoma should be publicly funded.
Thursday’s tie vote allows a lower court ruling to stand. Previously, Oklahoma’s state-level Supreme Court had barred the use of government funds to establish the St Isidore of Seville Catholic Virtual School, citing constitutional limits to the government’s role in religion.
But the US Supreme Court’s split vote on Thursday leaves an avenue open for other, similar cases to advance. With no decision from the highest court in the country, no new precedent has been set to govern funding for charter schools, which are independent institutions that receive government funding.
It is relatively rare, though, that a Supreme Court case should end in a tie vote. The Houston Law Review in 2020 estimated that there had only been 183 ties at the Supreme Court since 1791, out of more than 28,000 cases.
Normally, there are nine justices on the court’s bench — an odd number, to ensure that the judges are not evenly split.
But Justice Amy Coney Barrett recused herself from the hearings over the St Isidore school. Though she did not indicate her reasons, it is widely believed that Barrett stepped away from the case to avoid potential conflicts of interest.
Barrett has a close personal relationship with an adviser to the St Isidore school, lawyer Nicole Garnett. As young legal professionals in the late 1990s, they clerked together on the Supreme Court, and they eventually taught together at the University of Notre Dame in Indiana.
When US President Donald Trump nominated Barrett to the Supreme Court in 2020, Garnett even wrote an opinion column in the newspaper USA Today, praising her friend as “remarkable” and describing their lives as “completely intertwined”.
The Supreme Court’s brief, two-line announcement on Thursday acknowledged Barrett’s absence.
“The judgment is affirmed by an equally divided Court,” it read. “JUSTICE BARRETT took no part in the consideration or decision of these cases.”
That left the court split four to four, though the precise breakdown was not provided. Chief Justice John Roberts is thought to have joined with the three left-leaning justices on the bench to oppose the school’s use of government funds.
The Supreme Court currently has a conservative supermajority, with six justices leaning rightward.
In the past, the court has signalled receptiveness to expanding religious freedoms in the US, including in cases that tested the Establishment Clause of the US Constitution.
While that clause bars the government from “the establishment of religion”, what qualifies as establishing a religion remains unclear — and is a source of ongoing legal debate.
The Oklahoma case stretches back to 2023, when the Catholic Archdiocese of Oklahoma City submitted an application to open a taxpayer-funded charter school that would share Catholic teachings.
The school would have been the first of its kind, offering public, religious education online for children from kindergarten through high school. The plan was to open the following year.
The Oklahoma Statewide Virtual Charter School Board initially voted down the proposal in April, only to give it the go-ahead in June by a narrow vote of three to two.
That teed up a legal showdown, with opponents calling the school a clear violation of the constitutionally mandated separation of church and state. But supporters argued that barriers to establishing a Catholic charter school limited their freedom of religion.
Plans for the school even ended up dividing Oklahoma’s government. The state attorney general, Gentner Drummond, opposed the charter school as a form of “state-funded religion”. The governor, Kevin Stitt, supported the proposal. Both men are Republicans.
In Oklahoma, as in the majority of other US states, charter schools are considered part of the public school system.
When the case reached the state-level Oklahoma Supreme Court in 2024, that distinction became pivotal. The fact that St Isidore was a public — not private — school ultimately caused the court to strike it down, for fear of constitutional violations.
The judges ruled in a six-to-two decision that establishing St Isidore with state funds would make it a “surrogate of the state”, just like “any other state-sponsored charter school”.
The school, the judges explained, would “require students to spend time in religious instruction and activities, as well as permit state spending in direct support of the religious curriculum and activities within St. Isidore — all in violation of the establishment clause”.
The school’s backers appealed to the Supreme Court, leading to arguments being held in April. It was unclear at the time which way the high court seemed to be leaning, with Roberts pressing both sides with questions.
But conservatives on the Supreme Court’s bench seemed in favour of backing St Isidore’s appeal. Justice Brett Kavanaugh, for instance, argued that withholding taxpayer funds from the religious school “seems like rank discrimination against religion”.
“All the religious school is saying is, ‘Don’t exclude us on account of our religion,’” he said.
The left-leaning justices, meanwhile, indicated that a ruling in favour of St Isidore would pave the way for public schools to become religious institutions, a slippery slope that could require the government to fund faith-based education of all stripes.
On Thursday, the American Civil Liberties Union (ACLU), which has backed a separate lawsuit against the school, framed the deadlock at the Supreme Court as a victory for the separation of church and state.
“The very idea of a religious public school is a constitutional oxymoron. The Supreme Court’s ruling affirms that a religious school can’t be a public school and a public school can’t be religious,” said Daniel Mach, director of the ACLU’s Program on Freedom of Religion and Belief.
But proponents pledged to keep on fighting. Jim Campbell, who argued in favour of St Isidore on behalf of Oklahoma’s charter school board, noted that the court may “revisit the issue in the future”, given the deadlock.
“Oklahoma parents and children are better off with more educational choices, not fewer,” he said.
