The prosecution is vowing to appeal against her acquittal, but Amanda Knox is already on her way home.
The American left Rome for a flight bound for Seattle, via London.
Knox is free after four years in prison, after being cleared of killing British student Meredith Kercher in Perugia in 2007.
Her Italian boyfriend at the time, Raffaele Sollecito, was also acquitted.
Knox’s lawyer, Carlo della Vedova, said: “There is a tragedy of a young girl that was found dead, as well as two young kids that have been jailed for four years with no reason apparently. Plus there is another gentleman who has also been sentenced.
“So altogether it’s a sorrow. I think there’s no winner. It’s difficult to say that there is a winner in this case. We’re actually all a loser when there is a tragedy like this, and the media should have respected this more, I think.”
Despite being heavily criticised over the case, the prosecution said it would appeal against the acquittal to Italy’s highest court.
It is still not certain whether Knox would eventually be forced to return to Italy for any further appeal hearings. Rome and Washington do have an extradition treaty, but experts are divided on what would be the likely legal course of action.