. >> a little checking revealed it was a perfect, unasailable alibi.effrey wilson was innocent of murder, that is. but as for a three month affair with joan, wilson was very cooperative. he revealed every lurid detail. >> back in april they were probably meeting for sex about two times a week. in july and of course the murder occurred july 23rd, at least four times a week. >> now deputy d.a. billy wis p began to flip that idea of the love triangle motive on its head. by the way jeffrey wilson was talking, seemed to west the person with reason to kill david was not jeffrey, but joan. >> from jeffrey's point of view, he describes how she was in love with him, that she was not in love with her husband, that she didn't want to be with her husband, she financially could not afford to leave her husband. >> wilson said he kept telling her he was only in it for the sex, didn't want to runoff with her. but if secret sex was all he wanted, joan he said kept pushing for more. >> and the situation actually continued to escalate. i think it was around july 18th, ag