Prosecutors had presented several motives -- from robbery to tensions between the two girls -- but the judges and jurors decided there was no motive. The crime, they said, "happened at the spur of the moment in a drug-fueled escalation of a sexual assault."
Simon said the very fact that the Italian court dismissed the prosecution's varying theories for a motive should speak volumes about her innocence.
"Why would Amanda do such a thing without a motive?" he asked.
Simon said his client is doing her best behind bars.
"Under the circumstances we believe she's doing very well," he said. "I mean this is tough situation."
But the possibility that prosecutors may get their way and put Knox away for life is not something her parents are willing to accept.
"We will never leave her over there. She will come home no matter what it takes," her father Curt Knox said.
"Any parent would do that for her innocent child," Mellas said.
ABC News' Nikki Battiste contributed to this report