Washington — The Supreme Court on Wednesday appeared divided over efforts in Oklahoma to create an online Catholic charter school, a case that could open the door to public dollars flowing directly to religious schools.

A ruling in favor of the school, St. Isidore of Seville Catholic Virtual School, could lead to the country’s first religious charter school and upend laws in at least 45 states and the District of Columbia, as well as the federal charter school program, all of which require charter schools to be nonsectarian, Oklahoma’s Republican attorney general, Gentner Drummond, has warned.

Eight of the nine justices are considering the case, as Justice Amy Coney Barrett recused herself. Following arguments, it seemed likely that the outcome hinges on Chief Justice John Roberts, who focused on the level of state involvement in its charter school program during the arguments. If the Supreme Court deadlocks 4-4, it would leave intact the decision of the Oklahoma Supreme Court, which ruled that the contract establishing St. Isidore’s as a Catholic charter school was a violation of state and federal law.