>> stephen f. scharf. >> reporter: jody scharf was worth more dead than alive. hat jody feared stephen fight do something violent if she pushed for divorce. even so, marion said, jody was determined to get away from her husband. >> she was going to have divorce papers served on stephen and she was very afraid of it. >> reporter: yet, was stephen violent enough to kill his wife? an unlikely but powerful witness was about to testify against stephen scharf. >> i'm here for my mother. >> reporter: his own son took the stand against him. now a businessman, jonathan scharf painted his father as an angry, violent man who terrorized his mother. >> did you see tt abuse? >> i did. >> reporter: jonathan scharf said he realized his father had likely killed his mother only after that arrest in 2008. this videotaped interview shows him recalling the dark past for the first time to police. >> she got coffee thrown at her by him. >> reporter: now in court, he had even more to tell about his childhood. like the afternoon he sat cowering in the back seat of a car watching his moth