mistress at the center of that utah murder tria JUST CONVICTED martin MacNeill found guilty of killing his wife in her bathtub. Reporter: It was a circumstantial case, based on love, betrayal and... See More
mistress at the center of that utah murder tria JUST CONVICTED martin MacNeill found guilty of killing his wife in her bathtub. Reporter: It was a circumstantial case, based on love, betrayal and lies. But a jury reached a decision after one long night of deliberation. It maybe came down to one fact. If the jurors believed martin MacNEILL LOVED ONE WOMAN SO Much, he needed his wife out of the picture, completely. This is the woman prosecuto SAY martin MacNeill killed his wife to be with, gypsy willis. I never believed he was capable of such a thing. Reporter: You don't believe he killed michele? I really don't. Reporter: The allegation was, he loved you so much, that he wanted his wife out of the picture. So he could be with you. Martin had me anytime he wanted me. I have a hard time accepting that as an idea. Reporter: But a jury did accept it. And this weekend, convicted the utah doctor of murdering his wife, michele, in the couple's bathtub. When you heard that michele MacNEILL HAD DIED, DID ANY PART Of you think, now, I can have him to myself? That was not my thought at that time. He asked you to come to the funeral, did he not? I don't think he asked me to. I just wanted to go and show respect. Reporter: You wanted to go to the funeral of the woman whose husband you were having an affair with? I'm sorry that it was inappropriate. And that I had been acting selfishly. Reporter: You said you had great respect for michele MacNEILL? Yes. Reporter: How can you say you had respect for her when you were sleeping with him? Martin's wife was his choice. And I cared for martin. And so, by association, I had great respect for the other person that he would spend his life with. Reporter: Did you start thinking to yourself, okay, well, now, it's time for martin and I to move forward in our relationship? I would say, at the point when I came to stay with the MacNEILLS. Reporter: She said it was MacNEILL'S IDEA TO MOVE HER INTO The family home shortly after michele's funeral. Did you ever think to yourself, this would be a terrible idea, for me to come in and be the family nanny? Yes, I did. Reporter: And did you say to him, martin, no way. Are you kidding me? I did. I thought it would be better if things had -- everyonead time to regroup. He was rather insistent that he needed help. Reporter: Do you love him? I care about him on a deep level. I'm concerned about him. I hope he's well. He's a kindred spirit. And I loved him very much when we were together. Reporter: If you had never MET martin MacNeill, do you BELIEVE michele MacNeill would be alive today? I think michele died of natural causes. Reporter: If you had never met him, she would have died exactly the same way? I believe so. Gypsy willis was investigated in connection with the death of michele MacNeill. Her lawyer told me yesterday evening, that if prosecutors had any evidence against gypsy, there would have been two people on trial, not one. IS SHE IN contact MacNeill? She says it is not. But it's clear she has very strong feelings for him. When you talk to her about all of the evidence. I laid it out for her, what about this and this and this and this? Her response is, I don't buy . She goes through each piece of evidence and says why each one is not particularly significant. SHE SAYS THE martin MacNeill she knows, no way, no how, could have done it. A jury and a good amount of the american public disagree. Dan abrams, thanks very much.
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