but what was the motive for stephanie dittrick's murder? accounts gary ackley had a big mouth. >> prosecutors think in a moment of weakness, ackley told stephanie that he killed arlene. prosecutors found a witness who saw ackley and stephanie camping stth -- together on the 4th of july weekend. prosecutors believe ackley killed his childhood friend in order to silence her, burying her body in a shallow grave. again, leaving the tell-tale metal fragments behind. when he disposed of stephanie's personal items, he left his fingerprint on the shopping bag. >> i don't think there's anything i could say that would bother him because someone that can kill their girlfriend's mom and their kids' grandma is untouchable emotionally. so i wouldn't even try. >> a year after the crimes, gary ackley was convicted of two counts of first-degree murder and sentenced to life in prison without parole. despite the mountains of forensic evidence against him, arlene jensen's daughter julie refused to believe that ackley killed her mother. so after his conviction,