Knox, the Seattle-area coed convicted of killing her British roommate, Meredith Kercher, in Italy in 2007, is serving a 26-year jail sentence and trying to appeal her conviction. Her ex-boyfriend and another man also have been convicted in the slaying of Kercher, who was sexually assaulted and stabbed.
The New York Post said Knox's family invited Panettiere to Capanne prison in Italy last year to meet Knox before she portrayed her on the small screen.
"There were people who had mixed feelings about me meeting her, whether it had to do with my performance or their fear that she would tell me not to do it or say that she wasn't OK with it," the Post said Panettiere told reporters in a teleconference this week.
"To which I would respond: 'Look, they are going to do this film, whether it is me playing you or not. At least I can sit in front of you and tell you that I will do my best to do you justice.' It didn't work out because of scheduling. I would have had to go with her family to do that. She only gets to see her family for two days (a week.) So, to impede on that didn't seem like the right thing to do."
The movie is set to air on Lifetime Feb. 21, however, lawyers for Knox's family are fighting to block it from being broadcast because they feel it might jeopardize Knox's appeal, the Post said.