Director Tom McCarthy had said at the Cannes Film Festiva that Amanda Knox's case was an "initial inspiration point but not much beyond that."
"Stillwater" premiered at the Cannes Film Festival, starring Matt Damon as a father desperate to free his daughter from a criminal conviction in France.
Knox faced backlash from social media users who responded to her suggestion on Twitter late Tuesday night.
"These supporters of Mr. Raniere asked me to sign a petition," Knox explained in an email to an Albany publication. "I personally do not know enough about the case to make any judgments about whether his conviction is wrongful or not."
"Ask Amanda Knox" will be published in Westside Seattle, which is owned by her husband's family.
Knox has known both fame and prison in the years since she was wrongfully accused of murdering her roommate, Meredith Kercher, while studying abroad in Perugia, Italy in 2007.
Knox arrived in Italy Thursday to participate in a wrongful conviction panel planned for this Saturday.
See a new documentary about Amanda Knox, reminisce with Ferris Beuller or catch Hunger Games: Mockingjay Part 2.
Leonardo DiCaprio and Werner Herzog are among the Netflix nonfiction talent.
Knox said police coerced her to name the person who murdered her British flatmate Meredith Kercher.
Prosecutors ignored an 'absolute lack of biological traces' linking Knox to Kercher's murder.
An Italian court will soon decide whether to confirm Knox's conviction and 28-year sentence.
"It's not right, and it's not fair and I'm going to do everything that I can," Knox said