After the trial ended the actress said she has a "binder" packed with notes from her therapist, which she claims contains new evidence proving her allegations of physical and sexual abuse against Depp, despite the judge in the pair's case dismissing the documents.
Dror Bikel, a New York divorce lawyer, warned Heard could land herself in further legal trouble if she used a book to repeat her allegations against Depp.
He told OK!: "Depp and his attorneys will be reading and listening to everything that Heard states.
"If she crosses the line... there is no question that will be hit with another defamation suit and end up right back in court."
Heard said in her first public interview since her trial loss she was "terrified" about sharing her side of the story about her marriage to Depp after accusing him of physical and sexual assault.
She added to Dateline: "I know the scariest, most intimidating thing for anybody talking about sexual violence is not being believed, being called a liar, or being humiliated... I look forward to living my life and I have a long one, I hope, in front of me. And I will continue to walk through this with my chin up."