By Louise Boyle, Meghan Keneally and Rachel Quigley PUBLISHED: 10:11 EST, 28 February 2013 | UPDATED: 00:20 EST, 1 March 2013 The mother of slain high school student Lauren Astley cried on the witness stand today as she was asked to identify her daughter's ex-boyfriend, Nathaniel Fujita, as part of his murder trial. Fujita, now 20, is charged with killing Astley in July 2011 shortly after she had broken up with him and 'humiliated him'. Astley's mother, Mary Dunne, was one of the witnesses who testified on Thursday, talking about how in the months leading up to the killing, Fujita had changed from his outgoing former self into a withdrawn and aggressive.
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Nathanial Fujita killed his ex-girlfriend Lauren Astley in July 2011 but his lawyers say it was during a mental episode
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Astley's mother Mary Dunne testified on Thursday saying that she had to ask him to leave her daughter's graduation party weeks before her death
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Prosecutors are trying to prove that he knew what he was doing and actively tried to cover up his tracks
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Defense is arguing that he had a brief psychotic episode and are using his family history of mental illness
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