In phone conversations with Tracey, Karr expressed a desire to have Johnny Depp play him in a film version of his life.
"He even looks like me," Karr said of Depp, adding he was sure the star would choose to take on the role.
Karr also sent a detailed manuscript to Tracey about his relationship with JonBenet, insisting that he would have to maintain strict control over the movie rights.
Karr remained in custody in a Boulder jail Tuesday night, awaiting extradition to California where he will face child pornography charges.
Welner said Karr was an extremely rare case, because he had confessed not as a result of an interrogation or suggestion by police but on his own.
Welner said there was another unusual aspect to Karr's confession.
"A pedophile has a sexual fantasy and attraction to children. John Karr has sexual fantasy and attraction to children, but he became obsessed with celebrity victims -- people he didn't have an attachment to or a connection to."
Karr seemed determined that he would be known for his involvement in JonBenet's death, or at least in the Ramsey saga.
He told Tracey: "I love JonBenet … 'til this day I love her and I've loved her very much and I … played an unreal role in her life and her death (whispered)."
Less than two weeks after the world witnessed Karr's very public confession in Thailand, it seems like it was only a role, and one that was only real to Karr.
"It doesn't surprise me that a human being can develop a false belief or a false memory, and truly believe they did something they didn't do," psychologist Elizabeth Loftus said to ABC News.
She said that Karr could believe it so strongly and that he would pass a standard polygraph test.
"If he truly believes that he did this, then he would be able to pass a lie detector test," Loftus said. "Because the lie detection -- if in fact you believe in it -- measures the stress of a deliberate fabrication. … What we may have here is an honest liar."
Dr. Welner is chairman and founder of the Forensic Panel (www.forensicpanel.com), a forensic consulting group that provides peer-reviewed expert testimony in court cases. He is also developing an evidence-based test to assist criminal sentencing called the Depravity Scale, http://depravityscale.org, which invites Americans to participate in surveys that are used to form a legal standard of what represents the worst of crimes.