In addition, prosecutor Alessandro Crini told a court in Florence that Knox's boyfriend at the time, Raffaele Sollecito should be sentenced to 26 years in prison in Kercher's death, ANSA reported.
In 2009, Knox and Sollecito were found guilty in the death of Kercher, whom prosecutors said was killed in a sex game gone wrong. Their convictions were thrown out by an appeals court in 2011 but in March, Italy's top court quashed the acquittals and returned the case back to the appeal stage. Kercher and Knox were exchange students studying in Perugia and were roommates.
During the new trial, Crini contradicted earlier defense claims that no reliable trace of the victim's DNA was on a knife seized by police from Sollecito's home. Crini also repeated accusations from the original trial that a third person, Rudy Guede of the Ivory Coast, held down Kercher as he sexually assaulted while Knox and Sollecito repeatedly stabbed her.
Guede was convicted and is serving a 16-year sentence for the sexual assault and murder of Kercher.
The new trial opened in Florence in September and a decision is expected in January.