Sheriff Mike Linder said hundreds of individuals had been interviewed over the decades of investigations and several people had previously confessed to Fenner's murder. While speaking, Linder choked up several times.

"We had several people actually say they were responsible for it,” Linder said.

Detective Shane Bancroft said someone had confessed for the murder last week in a "round about way." At least five people have confessed to her murder over the years, he said.

"I’m going to say that we had about five to seven people through the years have either directly or indirectly confessed to this crime,” he said. “And of course every single one makes us perk up our ears.”

In March 2017 O'Neill walked into the Yellowstone County Detention Facility and asked to speak to deputies to confess to a crime. Then he told deputies and confessed to Fenner's murder. Deputies noted that O'Neill seemed to be "coming down off meth," according to court documents.

In a second interview with investigators, O’Neill again confessed to Fenner's murder. In an interview with the Yellowstone County Sheriff’s Office, O'Neill also confessed to attacking and raping the newspaper carrier, according to charges.