(PROVO, Utah) -- A Utah judge has decided that a once prominent doctor who was recently freed from prison for identity fraud will now stand trial for the murder of his wife, calling his actions surrounding her death "evidence of a guilty mind."
Martin MacNeill, 57, a doctor and former Mormon Sunday school teacher, served three years in a Texas federal prison for fraud and was released in July. Last month, MacNeill was arrested on murder charges -- the warrant alleging that he "intentionally overdosed" his wife, Michele MacNeill, after she had plastic surgery, because she had approached him about his alleged affair.
In a Provo, Utah, courtroom on Wednesday, all eyes were on Gypsy Willis, the woman who moved into the family's home as a nanny for his youngest daughter two weeks after Michele's death. Investigators say a year-long affair with Willis was Martin MacNeill's motive in the murder of his wife.
Willis testified that she met MacNeil online in 2005 and started a sexual relationship one year later. She also said he provided her with a credit card to help her get through nursing school. She testified she never thought MacNeill would ever leave his wife for her.
After the death of his wife, MacNeill and Willis were both convicted of identity fraud and served years in prison for stealing the identity of MacNeill's 16-year-old adopted daughter.
"In this case, the motive will sit well with a lot of jurors because it gives them a hook which that they can justify a conviction," Attorney Ronald Richards told ABC News, noting that the state will need to show that there's some conduct on behalf of the defendant that links him to the murder.
In court Thursday, the prosecutor referred to Willis as the "nanny with benefits."
Shortly after her testimony, the judge ordered MacNeill to stand trial for first-degree murder, calling his actions surrounding his wife's death "evidence of a guilty mind."
An initial autopsy report stated Michele MacNeill died of natural causes. However, authorities now believe Martin MacNeill drugged and drowned his wife, who was found unconscious in the bathtub.
MacNeill's frantic 911 call five years ago seems to indicate that he tried to save his wife after she drowned.
Susanne Gustin, MacNeill's defense attorney, says that he's no killer. "He's done some bad things in his life, but does that mean he's a murderer? No," she said.
MacNeill is expected to enter pleas to the murder charges on Oct. 22, at which time a trial date could be set.
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