Wednesday, police in California revealed that they noticed five years ago that Karr had a fascination with the JonBenet slaying, and told Boulder police at that time what they knew.
Sonoma County, Calif., police say Karr was also focused on several other cases involving children, including 1993's highly publicized abduction and murder of Polly Klaas of Petaluma, Calif.
Also Wednesday, an ex-wife of Karr, who married him when she was just 13 years old, said in an ABC "Good Morning America" interview that he used to tell her about fantasies he had about little girls. Quientana Ray also alleges that she was drugged and things were done to her without her knowledge.
Her parents, appearing on the same broadcast, said they discovered letters Karr wrote to their daughter that were signed "S.B.T.C." — the same initials found on a ransom note left in the Ramseys' home on the day JonBenet was killed.
They did not show the letters during the interview and it is not clear whether they still have them.
Karr's family is also in the spotlight – after hiring an actor, author and producer to represent them in any media deals and use the cash to help them find a top attorney to represent Karr.
Karr told reporters in Thailand last week that he was with JonBenet when she died and that it was an accident. His family contends he was with them in Georgia at the time of the Colorado killing.
Police investigating the JonBenet murder have yet to reveal the nature of the evidence that caused them to charge Karr with felony murder, first-degree kidnapping, second-degree kidnapping and sexual assault on a child.
Last week was the first time the public first heard his name as a suspect in the JonBenet killing. Within hours, it came out that police had been watching him in Thailand for months – and arrested him, according to one report, when they became worried he might pose a danger to children in that country.
It now turns out that Karr's name surfaced a lot earlier: in 2001, when Sonoma County detectives investigating Karr as part of a child pornography case phoned police in Colorado – to tell them of Karr's "apparent fascination" with the JonBenet Ramsey murder.
A statement released Wednesday by the Sonoma County sheriff's office says Karr did not appear then to have any special knowledge of the Ramsey murder.
Karr remains in custody in Los Angeles, where he was transported after his arrest in Thailand. He's awaitingto face murder, kidnapping and sexual assault charges in the Ramsey case. That might not happen until early next week, according to attorney Jamie Harmon, who is representing Karr along with Patience Van Zandt, who also represented him in 2001 when he was accused of possession of child pornography.
Larry Garrison, the actor, author and producer hired by Karr's father and brother to represent the family in any media deals - says that while the family's film and book rights are secured, no money has changed hands yet.
"They proclaim his innocence," says Garrison. "They feel he was not there at the time, that some of the statements made by the press are absurd."
The Karr family, he says, "are spiritually coming from the right place... They're not looking for money for themselves. They're looking to support John's boys' college education and to make sure all legal fees are covered."
Even if "we have to enact a law really quickly that would prohibit him from profiting from a book sale, movie deal, TV rights, anything," Paugh says.
Paugh also says that regardless of who the killer is, the death of JonBenet – who was hit over the head, strangled and sexually assaulted - "was no accident."
Investigators in Sonoma County, Calif., said Wednesday that they found out in 2001 that Karr was fascinated with both the Ramsey case and another high profile child murder: the 1993 slaying of Polly Klaas, who was killed after being snatched from her home in Petaluma, Calif.
California detectives say evidence of this fascination turned up in tape-recorded comments and e-mails attributed to Karr.
"In a few instances while he seemed to be wondering about the JonBenet Ramsey murder, he made uncertain allusions to placing himself in the killer's role," police say, in a statement released by the Sonoma County sheriff's office. "However, we never uncovered any 'confession' statements, overt murder evidence, or other indications that John Karr possessed secret knowledge that only the murderer of JonBenet Ramsey would know."
On the tapes, which have been aired by several broadcast media outlets, a man with a Southern accent is heard discussing the details surrounding JonBenet's strangulation: "She was in a lot of pain before she died and suffered and was tortured. There is physical evidence of that. What a shame. It's shameful. That person did that to the most beautiful girl in the world."
The Sonoma department also noted Karr made references to two other crimes in two different states, including a child killing and a child molestation. Information about Karr was provided to the investigating agencies in all three states, including Colorado, the department said.
The disclosure by the Sonoma County sheriff raises fresh questions about the work of Boulder authorities.
The police department in particular drew heavy criticism for allegedly failing to secure the crime scene, while former District Attorney Alex Hunter was accused by at least one investigator of trying to protect JonBenet's parents. Hunter stepped down and Mary Lacy took over as DA in January 2001 - a year marked more by libel allegations against former detectives and police officers than any public progress in the case.
"I worry that this information might have fallen through the cracks during the time the Boulder police and the DA's office were bickering about JonBenet," said former Denver prosecutor Craig Silverman. "This guy should have gone on their radar screen."
The pornography case in California remains open. Karr fled after being charged and an arrest warrant was issued. Sonoma County authorities have said they will allow the Ramsey case to be resolved before pursuing their case against Karr.
Boulder authorities have not revealed what evidence led them to go to Thailand to get Karr a decade after the slaying.
CBS News legal analyst Andrew Cohen said he doesn't consider what Karr said in Thailand to be a confession, and Karr is not going to be able to plead guilty right away in Colorado.
"To plead guilty and have the judge accept the plea, there has to be a factual basis for it," Cohen said. "Prosecutors have to be convinced of that, and so does the judge."
Defense attorney Van Zandt says she personally likes Karr and felt he was under stress when he made self-incriminating comments.
"He's tired," says Van Zandt. "I hope he's beginning to relax and feel better. But he's been through an awful lot. He's exhausted, he's terrified, he's overwhelmed, he's just about as stressed out as a human being can be."
Sheriff's deputies are monitoring Karr's mental state and physical safety in jail, where he has twice met with a psychiatrist and is under a suicide watch, with deputies checking on him every 15 minutes.
She adds that Karr's "incriminating statements were made days before I met him, so I can't say under what circumstances those were made," but that when she and Van Zandt spoke to Karr he was "lucid and clear."