did you kill lisa ziegert?behind bars. but despite the rock solid evidence against him, his confession, his dna, gary schara pleaded not guilty. the detectives had to get ready for a trial. after gary schara's arrest, we had to essentially work the case backwards. andrea canning (voiceover): that meant traveling to the west coast, where the scharas had lived briefly after the murder. we're trying to create a picture of who gary is and who gary was before he was arrested. andrea canning (voiceover): the detectives reviewed thousands of pages of court documents from the scharas' divorce and custody case, and they discovered a remarkable statement from joyce. she wrote, "gary claimed that he could only have sex with me if he was controlling, was wearing his batman costume, and held a knife to my throat. gary has proven himself to be vicious, and merciless, and often sadistic." at the time, schara denied it. but decades later, the similarity to lisa's brutal death was eerie. knife-related sexual violence was emergi