The murder of Miranda Fenner

The Fenner case had no viable suspect for nearly twenty years. O'Neill, who had never been on the detectives' suspect list, brought the case to a close himself. In 2016, while on a psychiatric ward in Spokane, Washington, he had tried to claim responsibility, but investigators dismissed him as noncredible because the details he offered were already public and he falsely claimed a second killing. In March 2017 he presented again, this time at the Yellowstone County jail, offering details that had not been made public. Detective Shane Bancroft was initially skeptical, describing O'Neill as upset, confused, nervous and polite. Under Montana law a confession alone cannot sustain a conviction, so investigators could not arrest him immediately and sent him home while they worked to verify his account. The corroboration did not come from physical evidence tied to Fenner. During his confession O'Neill also disclosed a separate September 1998 attack, the rape and attempted murder of a newspaper carrier in Billings; a DNA swab taken from him during the confession matched that separate crime. Because his account of one 1998 attack proved true, investigators came to believe his account of the Fenner murder. Bancroft testified that without O'Neill's own confession the sentencing hearing would never have taken place. O'Neill pleaded guilty to deliberate homicide on July 22, 2019, and on August 23, 2019, State District Judge Jessica Fehr imposed three concurrent life terms.