The draft order, which was not a ruling on the case itself, was obtained by online news outlet Wisconsin Watch.
The Supreme Court's seven justices, in a statement released with the investigative report, called the leak “a breach of trust the court had not experienced in its history.” All seven justices condemned the leak.
The leaked order in June came in one of two abortion-related cases before the court. The court also heard a second case challenging the 1849 abortion ban brought by Attorney General Joh Kaul. A ruling in that case is pending.
The court has yet to set a date for oral arguments in the Planned Parenthood case that was the subject of the leaked memo.
Investigators questioned 62 people, including all seven Supreme Court justices, staff, interns and people with access to the court during a two-week period in June from the date the draft was available until Wisconsin Watch published its article.
Network logs, including individual web histories, shared folder files, individual folders, and emails from all employees with access to the draft order were also reviewed, the report said.
Additionally, printer data was analyzed to see who may have printed off a copy of the draft order.
“All available leads have been thoroughly pursued, and no suspects have been positively identified at this time,” the report said. It added that there was no evidence that the leak was the result of a breach of the court's computer system.
The report did conclude that the draft order had been forwarded to the personal email account of Justice Ann Walsh Bradley, one of the four liberal justices on the court who voted to hear the abortion case.
Bradley's law clerk told investigators that forwarding important documents to Bradley's personal email account was standard operating procedure.
That was the only time prior to publication of the Wisconsin Watch article that the draft order was forwarded to an email outside of the state court system, the report said.
Bradley did not return an email on Wednesday asking about the report. Wisconsin Watch declined to comment.
Bradley is retiring at the end of her term in August. She is being replaced by Dane County Circuit Judge Susan Crawford, who won election to the court in April, ensuring that liberals will maintain their 4-3 majority.
Missing computer data hindered the investigation, the report said. The logs showing websites visited in the two weeks leading up to the Wisconsin Watch story about the leaked order were incomplete, the report said. Only logs from June 26 and June 27 were available, not from June 13 through June 26 as requested. The article was published on June 26.
The lack of those website visitation logs “significantly hampered the ability to thoroughly examine the circumstances surrounding the leak,” the report said. “The issue underscores the importance of proper data management, retention, and verification procedures, especially when such information is crucial for ongoing investigations.”
The court hired an independent investigator to look into the leak because the court does not have an independent law enforcement agency. However, the report did not identify who led the investigation.
Three retired police detectives were hired at a cost of $165,740 to conduct the investigation and write the report, a spokesperson for the state court system said.
Audrey Skwierawski, the director of state courts, said her office would be creating a task force to review the report's recommendations and propose strategies to reduce the risk of similar incidents in the future.
Investigations into the inner workings of the Wisconsin Supreme Court are rare and fraught.
In 2011, when Bradley accused then-Justice David Prosser of choking her, the Dane County Sheriff's Department led the investigation. That agency took over the investigation after the chief of Capitol Police at the time said he had a conflict. But Republicans accused the sheriff of having a conflict because he was a Democrat who endorsed Bradley.
The Sauk County district attorney acted as special prosecutor in that case and declined to bring charges.