The Heroes star took on the title role in Lifetime's Amanda Knox: Murder on Trial in Italy, which is based around the brutal killing of Knox's roommate, Meredith Kercher, in Perugia, Italy in 2007, and the subsequent trial.
Knox was found guilty of the killing and sentenced to 26 years in prison in 2009, but she took the case to appeal and her conviction was quashed earlier this month (Oct11).
Panettiere was watching the appeal case unfold on TV - and she hopes the 24 year old gets "a second chance at life" now she's returned to her native America.
The actress tells Access Hollywood, "I was on the edge of my bed, my eyes welled up when I heard the verdict read.
"It's hard for me because I played her. I do feel like I have a certain connection with her. It's difficult for me to say that I'm not excited to see a young girl get a second chance at life and she does have a second chance, and I hope she makes the best of it."