soon after he was arrested, kim williams was brought in for questioning. >> investigators spent hoursview. >> she was just not going to give up any information. she talked about her husband and what a great guy he was and how he wouldn't hurt anyone. >> then, an fbi interrogator, growing impatient, got tougher. >> he raised his voice with her and was telling her that she knew that those people had been killed. >> then she broke, and what she told them was startling. she said, not only did she know something about the murders, she helped her husband carry them out. now, during the penalty phase, prosecutors planned to use her testimony to make sure the jury would give him a death sentence. >> she led us to a lot of evidence. and i think it was important for the jury to see and have all their questions answered. >> he came up with the plan to dress like law enforcement. >> they were a husband-and-wife murder team, and they went through a dress rehearsal the night before the mcclelland murders. >> he was modeling it for me. >> describe to the members of the jury what he was modeling for