(PERUGIA, Italy) -- Amanda Knox, an American college student who is appealing her Italian murder conviction, was "extremely happy" Wednesday after hearing that a court-appointed panel of DNA experts concluded that key DNA evidence used to convict her may have been contaminated.
"She's extremely happy," said her father Curt Knox in an exclusive interview with ABC News. "It's a weight off of her shoulders... She knew she was innocent, but having independent experts say that the DNA evidence is unreliable and potentially contaminated is a big step towards bringing her home."
Knox, 23, has been in an Italian prison since her arrest in November 2007 for the murder of her British roommate Meredith Kercher. She and her ex-boyfriend Raffaele Sollecito, 27, were convicted in 2009 and Knox was sentenced to 26 years in prison. Sollecito was given 25 years.
The report filed Wednesday in a Perugia court by court-appointed forensic experts, and obtained by ABC News, give credence to the defense lawyers of both Knox and Sollecito, who had argued that the evidence against their clients had been contaminated by police during their investigation.
"When I got the news today, you know, it was extraordinary," her father said. "We're still very hopeful that the court will see all of these compounding things and free her in September."
"We are thrilled," Knox's mother, Edda Mellas, told ABC News from Italy where she is waiting to visit with her daughter in prison. "This is what our experts said all along. This is great news. We've always known Amanda is innocent."
The forensic experts were charged with examining the two main pieces of evidence in the case, Kercher's bra clasp and a knife found at Sollecito's apartment.
"One cannot exclude that the results obtained could have derived from phenomena of environmental contamination and/or contamination, which could have taken place in any of the phases of the evidence gathering and/or manipulation" of the evidence, the experts wrote in their conclusion.
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