The Supreme Court has not been able to determine who leaked a draft of Justice Samuel Alito’s opinion in Dobbs v. Jackson Women’s Health Organization, the court said on Thursday.

The unprecedented leak last May revealed that the court was privately poised to overturn the court’s landmark decisions establishing a constitutional right to an abortion. The court indicated on Thursday that investigators would continue to review some additional evidence, but the court’s two-page statement left open the possibility that the source of the leak may never be found.

The court’s statement denounced the leak as “a grave assault on the judicial process.” And a report by Gail Curley, the court official tasked with investigating the leak, suggested that the court’s document-handling policies should be beefed up to prevent future leaks. “If a Court employee disclosed the draft opinion,” Curley wrote, “that person brazenly violated a system that was built fundamentally on trust with limited safeguards to regulate and constrain access to very sensitive information.”

The court’s statement came eight-and-a-half months after Politico published Alito’s draft opinion on May 2, 2022. One day later, the Supreme Court confirmed that the leaked opinion was authentic, and Chief Justice John Roberts disclosed that he had directed Curley, who is the court’s marshal, to launch an investigation into the source of the leak.