Transcript for Couple Accused of Abducting, Killing Science Teacher

And now to the murder trial in Vermont. A husband and wife accused of abducting a local school teacher and mother. The husband standing trial separately. And his defense is saying his wife was the killer. ABC's Mara schiavocampo has the latest. Reporter: Though showing little emotion in court, 32-year-old Allen Prue is accused of a crime that's saddened a Vermont community and made headlines around the nation. The 2012 kidnapping and murder of a beloved science teacher and mother who's driveway was snowplowed. He told police they decided to go out Sunday night to get a girl. They wanted somebody to play with. Reporter: In opening statements, prosecutors telling jurors they lured 33-year-old Melissa Jenkins from her home with a phone call. Saying the car broke down and she agreed to help. And prosecutors saying that act of kindness cost her her life. She got out of her vehicle, and as she did, she was strangled and beaten to death. Reporter: Police found jenkijenk Jenkins' car abandoned, her 2-year-old son in the backseat telling officers someone pulled on mommy's neck. He pulled his head down towards his chest. Reporter: Prosecutors say he confessed to the crime. But now Prue is pleading not guilty. Saying he only confessed to protect his wife who they say is the true murderer and manipulated their husband who they say has a low I.Q. Patricia Prue strangled her because she had become obsessively jealous. Reporter: They say she made the phone call, convincing Jenkins to come to the aid. He could argue she did it all, get acquitted, and testify that he did it all. Reporter: They are being tried separately. Two defendants accused of one shocking crime. Testimony continues today. No word on whether Prue will take the stand. The trial is expected to last about a month. Now Patricia Prue is also facing first-degree murder charges. She has pleaded not guilty. Her trial is expected to begin next month.

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