 Several witnesses were called forward over the following two months, including an investigator who testified that Osborne had been influenced by an online chat-group of people “obsessed” with mass shootings, some of whom encouraged Osborne to commit one.Prior testimony from the investigator revealed that Osborne had been planning an attack for months through his internet searches, constituting premeditation.But on December 12 of that year, Osborne did plead guilty to the five counts of murder and attempted murder, waiving his right to a jury trial.