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• John Mark Karr, a school teacher in 1996, was brought to the attention of investigators in April 2006 by Michael Tracey, a University of Colorado journalism professor who had produced documentaries about the case. Tracey said Karr had reached out to him in 2002 and slowly a story emerged over correspondence about Karr "accidentally" killing a child he'd been sexually involved with. Authorities traced Karr's calls to Thailand, where he was arrested and confessed to accidentally killing JonBenét. Karr's family provided evidence to investigators that he had been with them in Georgia the night JonBenét died, and no charges were ever filed after DNA testing didn't link him to the crime.

"It's another bump in the road for us emotionally, but I think we saw Lady Justice put her gavel down today," Pam Paugh, Patsy Ramsey's sister, told CNN in October 2006 after Karr was cleared. "I don't think that this story is over yet, and I think, again, patience is the prudent thing to desire at this point."

• Gary Oliva was named by 48 Hours Investigates in August 2002 as someone who had been investigated after it was learned he may have been near the Ramsey home the night of the killing and was spotted at a candlelight vigil for JonBenét on the one-year anniversary of the crime. The show reported he had called a close friend sometime after her death and sobbed that he had "done something horrible." In a jailhouse interview included in the show, Oliva denied being involved, saying, "I believe she came to me after she was killed and revealed herself to me. I'd like to see a memorial set up for her. I haven't seen that, anywhere."

Oliva was arrested on charges of possessing child pornography in June 2016. Boulder City spokeswoman Sarah Huntley told the Daily Camera, "The police department is certainly very familiar with him, both because of the investigation that was done in the context of the Ramsey case, and because of his criminal history and the fact that he is a registered sex offender."

She continued, "The police department diligently investigated these current allegations and believes there is probable cause to support the arrest. But we're currently not comfortable ruling anybody out as a suspect, or ruling anybody in as a suspect, in the Ramsey case."

• Ollie Gray, an investigator hired by the Ramseys who continued to look into the case on his own, became convinced that Michael Helgoth was the killer. Helgoth's family owned a scrap yard on the outskirts of Boulder at the time. John Kenady, who worked with Helgoth, had told In Touch Weekly in April 2016 that he had heard that a tape existed of Helgoth saying he killed JonBenét. Kenady said he reached out to police about 20 times in the months following the killing to tell them about Helgoth but never got any substantive response.

"You have to look for something in order to find something, and unfortunately for this particular case, you had a totally inexperienced police agency," Gray said on the Today show in May2016. "There are probably three or four people that should have been investigated earlier and still need to be investigated. The latest development in this particular case as far as I'm concerned is Michael Helgoth. He was basically a hell-raiser."