Independent forensic investigators in Italy have concluded that much of the DNA evidence used to convict American student Amanda Knox and her co-defendant of the 2007 murder of her British roommate is unreliable and possibly contaminated.
In a report Wednesday, the court-appointed experts said that DNA testing used against Knox and her former boyfriend, Raffaele Sollecito, in their trial was below international standards.
They were convicted of sexually assaulting and killing Meredith Kercher in what prosecutors say was part of a drug-fueled sex game that turned violent. Both Knox and Sollecito were sentenced to lengthy prison terms, but have denied the accusations against them.
A third person, Rudy Guede, was also convicted in the case and testified earlier this week at an appeal trial that Knox and Sollecito were the only ones to blame for the death of the 21-year-old Kercher.
Prosecutors have contended at the first trial that Knox's DNA was found on the handle of the knife believed to be the murder weapon and that Kercher's DNA was found on the blade. They said Sollecito's DNA was found on the clasp of Kercher's bra.
But the forensic experts say that the genetic profile attributed to Kercher is “unreliable” and that the results of tests on both the blade of the knife and the bra clasp may have been contaminated. The two investigators are expected to testify about their findings at a court hearing in late July.
Guede's statement implicating Knox and Sollecito was in a letter read to the court on Monday as he sat on the witness stand. The statement contradicted earlier testimony in which two convicted Italian criminals testified that Knox and her Italian boyfriend were innocent of the murder.
Mario Alessi, serving a sentence for kidnapping and killing a child, had told a court earlier that Guede had spoken to him about the murder when they shared a cell at Viterbo prison.
Guede has denied making any such statements.
Luciano Aviello, in prison for his ties with organized crime, testified that his own brother killed the young British student during an attempted theft.