Investigators have yet to piece together why Tyler Robinson allegedly scaled a rooftop at Utah Valley University during an outdoor event and shot Charlie Kirk in the neck. WASHINGTON: The man arrested in the killing of right-wing activist Charlie Kirk is not cooperating with authorities, but investigators are working to establish a motive for the shooting by talking to his friends and family, Utah Governor Spencer Cox said on Sunday (Sep 14). Cox said the accused gunman, Tyler Robinson, 22,