Lawyers for Knox, 24, a former University of Washington student, and Raffaele Sollecito, 27, have submitted an independent report to the court in Perugia in which experts say the DNA cannot be trusted, the Italian news agency ANSA reported. Prosecutors say the DNA of both Knox and her roommate, Meredith Kercher, were found on a knife believed to be the murder weapon and Sollecito's DNA was on one of Kercher's bra straps.
Knox was sentenced to 26 years and Sollecito to 25 for killing Kercher. Knox and Kercher, a student at the University of Leeds in Britain, were both in Perugia as exchange students.
Prosecutor Giancarlo Costagliola called the report a "scientific falsification of reality." He also urged the court to show consideration to Kercher's parents, describing the student as a "serious and discreet girl."
Knox's family expressed optimism. Stepfather Chris Mellas told the British newspaper The Guardian Thursday Amanda Knox is beginning to think the court will throw out her conviction.
"She's starting to think, maybe, this time she can actually do it," Mellas said. "She's allowing herself just a little bit of hope."
One of Knox's supporters, retired FBI Agent Steve Moore, said nothing in the original trial verdict makes sense if the DNA doesn't hold up.
A third person, Rudy Guede of Ivory Coast, also was convicted of Kercher's slaying and sentenced to 16 years. Guede also says he is innocent, while lawyers for Knox and Sollecito suggest he was the sole killer. Prosecutors say Kercher died resisting a drug-fueled sex game.