For obvious reasons, Knox's parents are not huge fans of the Italian justice system. Their latest encounter is unlikely to improve their opinion. Curt Knox and Edda Mellas, who divorced when Amanda was a young child, now face charges of their own.
When Amanda Knox was in court facing the murder charge, she insisted that she had been beaten - hit on the head - by Italian police during her interrogation. The police have always denied the allegation.
Amanda was interrogated for nine straight hours in one session, and finally signed an incriminating statement at 5:45 in the morning.
"I was very very scared, because they were treating me so badly and I didn't understand why," she said in court.
In an interview two years ago with the London Times newspaper, Amanda's parents were quoted repeating the beating allegation.
"Amanda was abused physically and verbally," her parents told the paper. "She told us she was hit in the back of the head by a police officer with an open hand, at least twice. The police told her, 'If you ask for a lawyer, things will get worse for you.'"
Now the police in Perugia, where the murder of British student Meredith Kercher took place, have started legal proceedings against Amanda and her parents, who live in Seattle - accusing them of slander.
"In Amanda's circumstance, she was merely telling what she experienced, not intending to slander people, but to explain why she was in the circumstances that she is in," says Curt Knox.
Amanda at the beginning of her own slander case.
"She was just stating what she experienced during that overnight interrogation and she was just defending herself," says the father. "With respect to Edda's and my slander charges, I believe those will get thrown out and this is nothing more than a harassment."
However, CBS News legal analyst Jack Ford says the Italian justice system -- which has come under constant and relentless attack from the Knox family and their lawyers -- may just be pushing back against the pressure.
The slander charges may seem "a bit like overkill from our perspective, but from their perspective, they're saying if she's saying stuff about them that's a lie, 'we want our day in court.'"
Tuesday's court session was just a pre-trial hearing. The case against Mr. Knox and Mellas is set to resume in mid-October, the same month Amanda Knox's appeal against her murder conviction is due to start.
Ford tells CBS' "The Early Show" that, if Amanda is convicted of defamation, it could add as long as six years to her prison sentence in Italy. If her appeal on the murder charges is successful, she could even end up in prison in spite of her exoneration in the killing, based on the new police lawsuit.