Transcript for DNA Results a Key Piece of Evidence in Amanda Knox Case
Amanda knox is staying far away from the court in italy this morning where she is being retried for the murder of her roommate. Now, just coming to light, dna results on a key piece of evidence, a finding that could weigh heavily in her defense. Nicki batiste has the story. Reporter: The latest chapter in amanda knox's six-year-long legal battle may be taking a turn in her favor. No matter what people say, i didn't do it. Reporter: Friday, italian forensic experts began tests on a crucial and previously untested piece of dna found on the alleged murder weapon, a kitchen knife. Where meredith kercher was not on the blade. Something the prosecution was hoping for. Their hopes have been dashed. Reporter: Ted simon, a lawyer for knox, says tests of skin cells found on the knife are not a match for the victim, meredith kercher. The results could refute the prosecution's claim that the knife was used to kill kercher. They made these findings. But they're unofficial yet, until they submit their findings with the court. Reporter: Knox is steering clear of the courtroom during her new trial. She's staying in seattle and going to college. Knox sat down with me just after the supreme court overturned her acquittal in march. I had panic attacks and just broke down. I couldn't breathe. How do you -- how do you deal with it when it's too much for even you? Reporter: Knox says even after two years of freedom, she didn't escape the psychological prison she still endures. The feeling of helplessness, that's the major thing. Reporter: For "good morning america," nicki batiste, abc news, new york.
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