The sentencing report released by the Court of Cassation refers to a conversation Knox, a University of Washington student who was spending a year in Perugia when she was arrested, had with her parents during a prison visit, Seattlepi.com reports.
"I was there," she allegedly said.
Her statement was not used as evidence at her trial. It was included in a sentencing report on Rudy Guede, an immigrant from Ivory Coast who was tried separately from Knox and her former Italian boyfriend, Raffaele Sollecito.
Knox and Sollecito say Guede killed Meredith Kercher, a university student from Britain, in 2007.
Guede admitted to police he was at the house but maintains he was in the bathroom when Kercher was killed. He said he overheard her having an argument with another woman and then came out to find Kercher dead and a man, Sollecito, who told him "Black man found, black man guilty."
Knox was sentenced to 26 years in prison, Sollecito to 25 years and Guede 16.