This warped version of her entered into the courtroom, compromising the result of the trial, she said.

The most important lesson she had learned, she said, was that it was easy for the public to distort defendants into monsters. “It’s easy to see what we want to see,” Ms. Knox added, reducing criminal cases to “black and white stories populated by demons and saints.”

The three-day festival was organized by Italy’s Innocence Project and the Criminal Bar Association in Modena to discuss “complicated themes” on criminal justice, said Luca Lupária Donati, a law professor at Tre University in Rome and the founder and director of the Italian Innocence Project. Judges and prosecutors were invited to attend.

Mr. Lupária said in an interview in Rome that the issue of wrongful conviction and miscarriages of justice was especially important “in a moment of populism, where the theme of the death penalty was rearing its head in Europe,” where it does not exist.

“It can take 100 to 200 years to achieve some legal rights but a day to lose them,” he said.

Ms. Knox’s case was particularly divisive, stirring passionate debate on her innocence in Italy and the United States. Hordes of news cameras and journalists followed the case as it bounced from court to court. Benedetto Lattanzi and Valentino Maimone, the co-founders of Errorigiudiziari.com, an archive that tracks judicial errors in Italy, said that whenever they posted something about Ms. Knox, she was immediately attacked on social media by Italian haters.

“We’re still stunned that so many years later there’s still this hatred, this loathing,” Mr. Maimone said.

Since her return to the United States, Ms. Knox has been involved with the Innocence Project and has hosted a Facebook series and a podcast on true crime for Sundance on justice issues. At a seminar on Friday in Modena, she hugged fellow exonerees Peter Pringle, who was wrongfully imprisoned on a murder charge in Ireland for 15 years, and Angelo Massaro, who was wrongly imprisoned for 21 years in Italy on a murder charge.