what possible motive would bobby low have to want deede out of the picture? >> there was no motive i could determine whatsoever. >> low provided investigators with two important clues. first he said while he was at deede's that night, her dogs had all started barking at something outside, as if someone were lurking and the next morning he discovered someone keyed the side of his ford explorer, leaving a long scratch. >> which suggests what, someone's following them on that date? >> absolutely. that's what it meant to me. >> but who was following deede and bobby? who was that angry. that act of vandalism pointed away from bobby low. >> i was an investigator for several years. i've never known anybody to vandalize their own car. >> that kind of thinking is what would make it a perfect alibi. >> sure, sure. if he's sophisticated enough, but his background indicated that he was a well liked guy, kind of successful himself, and didn't have a lot of enemies. >> and then, even as investigators looked at suspects, came the news that all who knew deede had at once hope