DNA evidence used to convict Amanda Knox of the murder of her British roommate was unreliable and had potentially been contaminated, a report has concluded.
The finding by two independent experts was requested by Knox's defence team and is regarded as a boost to her hopes of getting her murder conviction quashed.
Knox was convicted in 2009 of sexually assaulting and murdering Meredith Kercher – with whom she shared an apartment while both were exchange students in Perugia – and sentenced to 26 years in prison. Her co-defendant and ex-boyfriend, Raffaele Sollecito, was sentenced to 25 years but both have protested their innocence and are appealing.
Edda Mellas, 23-year-old Knox's mother, described her daughter as "very happy" after learning of the review's conclusions. Luciano Ghirga, the US student's lawyer, said: "We've been waiting for three years for this. It finally came."
Prosecutors maintained in the first trial that Knox's DNA was found on the handle of a kitchen knife they believed to be the murder weapon, and that Ms Kercher's DNA was found on the blade. They say Sollecito's DNA was found on the clasp of Ms Kercher's bra. The defence disputed those findings and the appeals court granted an independent review. A similar request was turned down in the first trial.
Experts Stefano Conti and Carla Vecchiotti, of Sapienza University in Rome, said in their report that the genetic profile attributed to Ms Kercher is "unreliable" and cannot be attributed with certainty. They said results may have been contaminated on both the blade and bra clasp.
Referring specifically to samples from the blade they said: "We believe that the technical tests are not reliable." They added: "It cannot be ruled out that the result obtained... may stem from contamination." Tests, they said, fell below internationally accepted standards.
In the 145-page report, which they will present in court on 25 July, they were also critical of the treatment of the sample from the bra strap: "The exhibit was retrieved 46 days after the crime, in a context that was highly suggestive of ambient contamination."
However, the review agreed with the original tests in saying the genetic profile on the knife's black plastic handle could be attributed to Knox. The knife was found at Sollecito's apartment.
Francesco Maresca, the lawyer for Ms Kercher's family, said after learning of the report: "We are surprised and stunned by such a categorical judgment." He added that he would seek an explanation for "such drastic conclusions".Reuse content