Prosecutors countered, however, that DNA evidence placed them at the scene of the murder. A key piece was Sollecito's DNA on a clasp that had been cut away from Kercher's bra during the murder. Knox and Kercher's DNA were found mixed in blood in the bathroom. And DNA from Knox and Kercher was found on a knife in Sollecito's apartment.
Prosecutors also cited Knox's odd behavior in the days after the killing, her snuggling with Sollecito and doing a cartwheel while waiting to be questioned by police. They argued that it was indicative of a cold and unfeeling woman.
Defense lawyers, however, said the evidence was badly handled that allowed for contamination and the amount of some of the DNA was so minute that there wasn't enough to do a second, confirming test. The blade of the knife, they said, was not compatible with the cuts on Kercher's neck.
In addition, Knox hadn't behaved like a guilty murderer, calling the police to the scene and refusing offers from family members to have a have from the violence back home in Seattle or with an aunt in Germany. Instead, her lawyers said, Knox stayed to help the police.
The defense also argued that they had already convicted the real murderer, Guede, who has been sentenced to 30 years in prison for his part in Kercher's killing. Guede's DNA was found on Kercher's body along with his bloody palm print on her pillow. Guede is appealing his conviction.
A serious hurdle for Knox was an admission she made during an all-night interrogation police that she had a vision that she was at the cottage during the murder. She later retracted that statement, saying it was made under duress when the Italian police were aggressive with her and hit her in the back of the head.
In addition to the murder, Knox simultaneously faced a civil trial in which the prosecutors sought $12 million in damages for the Kercher family, and a slander trial.
The slander charge came out of her odd "vision" confession. She told police at the time that Patrick Lumumba, a bar owner she worked for, was also at the crime scene. Lumumba was arrested, but later released and he sued Knox.