By Associated Press Reporter The defense attorney for a man charged with raping and strangling to death a University of New Hampshire student spent his first day cross-examining the state's star witness trying to convince jurors she was possessed by imaginary characters she had created. Defense attorney Joachim Barth also asserted the witness, 20-year-old Kathryn McDonough, changed her story and shifted the blame from herself to defendant Seth Mazzaglia, her ex-boyfriend, just to get a reduced sentence. Mazzaglia is charged with first-degree murder in the October 2012 strangulation death of 19-year-old Elizabeth ‘Lizzi’ Marriott, of Westborough, Massachusetts. He has pleaded not guilty. Prosecutors say he and McDonough dumped Marriott's body in a river and it hasn't been recovered.
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Kathryn McDonough, 20, was cross-examined Thursday by in 31-year-old Seth Mazzaglia's trial over strangulation death of Lizzi Marriott in 2012
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McDonough claims she watched as Marriott was killed after she allegedly rebuffed McDonough's advances
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Defense attorneys replayed a scene in which McDonough told a friend she was under control of separate personality and could not recall murder
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Mazzaglia's attorneys say that McDonough carried out the killing and he covered for her because he was obsessed with her
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McDonough is serving a prison sentence for lying to investigators about Marriott's disappearance and death
@placeholder told jurors during his opening statement May 28 that McDonough had ‘a real problem.