His parents said they were so concerned that they called police. Officers who showed up at Rodger’s doorstep for a mental health check in April, however, found a well-mannered if shy young man whom they concluded posed no risk. They hadn’t seen the videos, and by the time law enforcement had, it was too late: Rodger had gone on a deadly rampage. The sheriff’s office “was not aware of any videos until after the shooting rampage occurred,” Santa Barbara County Sheriff’s Office spokeswoman Kelly Hoover said. Sheriff Bill Brown has defended the officers’ actions, but the case highlights the challenges...