The Supreme Court said Thursday an eight-month investigation that included more than 120 interviews and revealed shortcomings in how sensitive documents are secured has failed to find who leaked a draft of the court’s opinion overturning abortion rights.

Ninety-seven employees, including the justices’ law clerks, swore under oath that they did not disclose a draft of Justice Samuel Alito’s opinion that overturned Roe v. Wade, the court said.

It was unclear whether the justices themselves were questioned about the leak, which was the first time an entire opinion made its way to the public before the court was ready to announce it.

Politico published its explosive leak detailing the Alito draft in early May. Chief Justice John Roberts ordered an investigation the next day into what he termed an “egregious breach of trust.”

On Thursday, the court said its investigative team “has to date been unable to identify a person responsible by a preponderance of the evidence.”

The investigation has not come to an end, the court said. A few inquiries and the analysis of come electronic data remain.