#317 - When a pattern emerges in criminal investigations, it often becomes the strongest lead. In Southern California, that pattern pointed to a serial sexual offender who used a knife to control his victims and left DNA behind at multiple scenes. For years, the DNA sat unmatched. Today’s episode examines the San Diego Knifepoint Rapist case, the forensic evidence that connected the assaults, and how modern genetic genealogy transformed a cold case into a solved one.