This is basically everything I've heard/read about this case. If you're an accomplice to a crime, whether you've physically committed any acts is irrelevant. If she didn't kill Meredith Kercher, but stood idly by while the other person DID, and she didn't make any attempts to stop him, call the police.....anything at all to save her life, she's a murderer just the same. The same as if you and a buddy drive down to the liquor store and while you're sitting in the car, he holds the place up and jumps in the car and tells you to speed away - the minute you drive away, you're now the getaway driver in an armed robbery. It doesn't matter if you didn't know what your buddy's intentions were before he got out of the car.
She deserves to sit in prison. If she or her family doesn't like that, maybe she shouldn't have been complicit in someone's murder.