She'll never leave the US, rightfully so imo there's next to no evidence connecting her or Sollecito to the crime, they have the killer in Rudy Guido imo, no evidence as far as i'm aware that there was more than one killer. The only question to be asked of Knox and Sollecito is whether they knew it was going to happen or that they witnessed it, because i don't think they're completely innocent. I think that Guido was the one that murdered her though.