By Jean Casarez CNN

(CNN) -- Maybe it's the time of year she was killed.

Maybe it's the fact that her parents were considered suspects and later cleared.

Maybe it's because the murder of a 6-year-old beauty queen has never been solved.

Twenty years later, the public continues to be captivated by the JonBenet Ramsey case.

A short life in the spotlight

1996 started as a magical holiday season for the Ramsey family. John Ramsey's company Access Graphics had grossed more than $1 billion in revenue, and it was big news in the Ramsey's community of Boulder, Colorado.

JonBenet had been in the local Christmas parade about a week earlier on a float with her name on the side, something John Ramsey now says was a mistake.

JonBenet, a former Little Miss Colorado, was accustomed to the spotlight, even at her young age. Her mother Patsy, a former Miss West Virginia and contestant in the Miss America pageant, encouraged JonBenet to participate in pageants and as John Ramsey told me, JonBenet had won most of the them.

"Patsy and I used to say, she needs to lose some of these pageants because she needs to understand you don't always win," Ramsey said in an interview for the CNN Special Report, "The Murder of JonBenet." "We wanted JonBenet to have that opportunity to experience her bent towards performing and singing. But we didn't want her to win, necessarily. Because we wanted her to understand life. You don't always win."

Christmas morning was always exciting for JonBenet and her 9-year-old brother Burke, and December 25, 1996, was no exception.

Santa Claus brought JonBenet a brand new bicycle. She and her father tried it out that afternoon before the family went to dinner at a close friend's home.

When the Ramseys returned that evening, JonBenet was already sleeping, her parents said, and John Ramsey carried her up to her bedroom. Patsy Ramsey helped put her to bed.

Little did the family know that would be the last time they would see her alive.

A questionable ransom note

December 26 was going to be a big day for the family. They were going to fly in John Ramsey's private plane to Michigan and meet up with his older children, and then the entire family was going to take a Disney cruise.

Patsy and John Ramsey got up early. Suddenly, John Ramsey heard a scream from downstairs.

That scream was from Patsy Ramsey. She found an elaborate, three-page, handwritten ransom note, written by someone who claimed to have kidnapped JonBenet. The letter, which was addressed to John Ramsey, said the kidnappers were a foreign faction demanding money for the return of JonBenet.

John Ramsey told his wife to call 911.

From that day forward, life changed for the Ramseys, and the country would soon learn about a murder mystery for which its fascination would only grow with time.

The ransom note asked for $118,000, which was the exact amount of John Ramsey's bonus. The note went on to say he would get a call by 10 a.m. the next day.

John and Patsy Ramsey waited at home for the call. It never came.

Law enforcement and friends drifted in and out of the home all day. Finally in the afternoon, Ramsey says Linda Arndt, one of the main detectives, told him to search the home to see if there was anything suspicious.

Ramsey and his friend went down to the basement, where he discovered a horror when he opened the cellar door, he recalled.

"It used to be an old coal room for that house. It was an old house. I opened the door and of course JonBenet was there. I saw her immediately. And it was a rush of relief, I thought, God, I found my child. And then I pretty quickly realized that she may not be alive."

JonBenet was found with a garrote fashioned out of rope embedded deep into her neck. The same rope was around one of her wrists. At the end of the garrote was a broken paintbrush that appeared to be from Patsy Ramsey's art set.

One mystery was solved -- JonBenet hadn't been kidnapped. But another had just begun. This would now be a murder investigation.

The focus turns to the family

The pivotal question was who could have done this to an innocent little girl. Investigators immediately turned the focus on John and Patsy Ramsey.

And the ransom note only raised more questions. Why would someone write a ransom note if there wasn't a kidnapping?

When detectives asked John Ramsey for handwriting samples, he gave them the notepads he and Patsy Ramsey kept by their telephone. The pages for the ransom note had been torn from Patsy Ramsey's notepad.

As all attention turned to the couple, video surfaced of JonBenet in beauty pageants -- a little girl with makeup and heels.

The nation was now fixated and seemingly couldn't take its eyes off JonBenet and her parents.

It only got worse from there.

John and Patsy Ramsey did not sit down for a formal interview with police for months after JonBenet was killed. Leaks began to surface from within the Boulder Police Department saying the family was uncooperative.

Ramsey, however, tells a different story.

He says issues began when Ramsey attorneys asked for transcripts of initial interviews the couple had given to law enforcement.

"And not only would they not give them the transcripts of our previous interviews, they refused to release JonBenet's body for burial. And that just incensed our attorneys, because it's wrong," he says.

"So that sort of started this whole, 'we don't trust you, you don't trust us environment.' Well, the attorneys got the body released from the police so we could bury her. And after the funeral, we went back to Boulder to help the police and let Burke finish out his school year with his friends. Because we thought that'd be best for him. And we wanted to help the police."

Ramsey says the couple completed about 150 hours of police interviews.

Private information becomes public

Details of what should have been a nonpublic murder investigation became front page news, and the public soon realized there were problems with the case.

It was undisputed even by those in charge that the crime scene had been compromised on December 26 because so many people were in and out of the home.

Potential evidence was not collected in a timely manner to eliminate the likelihood of contamination.

Forensic pathologist Dr. Daniel Spitz told CNN that all those mishaps hurt the investigation's conclusions from day one.

For example, Spitz noted one aspect that could have been relevant to JonBenet's cause of death.

John Ramsey told CNN that upon finding his daughter in the basement, he removed duct tape from her mouth and threw it down on the basement floor.

Spitz says that act alone, unintentional by all accounts, prevented a forensic accounting of whether that duct tape was a mechanism of death.

"The duct tape on the mouth may have been part of the death sequence if, in fact, it was covering the nose and mouth together. We don't really know that."

Dr. John Meyer, who performed the autopsy, concluded JonBenet's cause of death was suffocation in conjunction with forcible trauma to her skull.

Despite issues with the crime scene investigation, Spitz says one of the best documented pieces of work in the JonBenet case is that autopsy report.

"I think the autopsy report is probably the least disputed in terms of the cause of her death and the injuries that she sustained.

"It's all of those other questions that have been evaluated and theorized and speculated about that still are not known and, unfortunately, may never be known," he says.

While the Ramseys were slow to talk formally with law enforcement, they did appear on CNN, one of the first errors the family made, according to John Ramsey.

"That was a mistake. We had our close friends who just insisted we do that. The media's focusing on you as the killers, and they're criticizing Boulder and you need to go out there and show people who you are," he says. "And they kept insisting, you've got to do it. You've got to go on TV."

The appearance sent an incorrect message to the public that they would talk to CNN but not police, Ramsey said.

The grand jury convenes

Two years after JonBenet's killing, with the case no closer to being solved, Boulder's district attorney convened a grand jury in 1998.

Once again, the murder was front page news, but now it was the images of each grand juror, whose identity is always confidential, revealed as proceedings were on going.

Nonetheless, for the next 13 months those jurors heard testimony from law enforcement as well as civilians.

John Ramsey's children, including Burke, who was in the home when his sister was killed, took the stand.

John and Patsy Ramsey were not asked to testify.

At the conclusion of the proceedings, Boulder County District Attorney Alex Hunter convened a press conference broadcast live nationwide.

Hunter announced there would be no charges in the death of JonBenet.

Local reporter Charlie Brennan says it left the community hanging.

"It was a highly unsatisfying conclusion for I think both the media and members of the community because it felt like there were ... clearly things being left unsaid."

Brennan's hunch was right. As time went on, he started to hear some rumors, and his sources told him there had likely been an indictment.

Brennan contacted every grand juror he could find, explaining to them the historical importance of the public finally knowing what they actually decided.

"I was able to persuade several grand jurors to confirm for me the fact that they had voted to indict."

Brennan broke his news in January 2013 in Boulder's local newspaper, The Daily Camera.

From there, Brennan filed a lawsuit to get the grand jury indictment made public.

The judge partially agreed, releasing four pages of the indictment, while keeping the remaining 14 pages under seal.

Stan Garnett, Boulder's current district attorney, told CNN that one day before being sworn in as district attorney of Boulder in 2009, he was told in a top-secret meeting about the unanimous decision in favor of charging John and Patsy Ramsey that had been made by the grand jury in 1999.

Garnett says Hunter's decision made history for Colorado. "There had never been a circumstance quite like this. A grand jury had returned a true bill, the DA had refused to sign it and that it remained secret for a long time and eventually its existence became known.

"We were treading on new ground."

With this new information, the mystery about what happened to JonBenet was as perplexing as ever.

John Ramsey has his theory: "They just wanted to go home."

"We were told that they were given, like, five choices, probably one of which was first degree murder. They'd been sitting there for 13 months. Probably wanted to get out of there."

The grand jury returned true bills of indictment on two counts involving the Ramseys: child abuse resulting in death and accessory after the fact to first degree murder.

The DNA analysis leads to questions and an apology

The DNA analysis in this case has been debated and disagreed upon since the original testing was done shortly after the killing.

Forensic scientist Dr. Angela Williamson, who performed some of the forensic testing, told CNN that early DNA testing was done of the crotch of JonBenet's panties, where her blood had been found. The result was a very strong profile, she says, of an unknown male that could not be matched to anyone who had been near the scene or who had handled her body. It was also not a match to John Ramsey.

Williamson noted how thorough the DNA testing was. "They even compared this DNA profile with the man whose autopsy had been performed right before JonBenet's."

It was determined that quite possibly the unknown male DNA could have come from a factory worker where the underwear was made, because JonBenet's underpants were right out of the package -- brand-new that Christmas. Those unanswered questions remained for the next decade.

In 2006, the case made headlines again because of an American teacher in Thailand who confessed to JonBenet's killing. John Mark Karr was brought to Boulder, but because his DNA didn't match that unknown male DNA, he was ultimately released. No charges were filed and authorities now believe he merely was seeking attention.

Also in 2006, a significant forensic finding was made by Williamson, who was employed by Bode Laboratories at the time.

She was approached by Boulder law enforcement to do touch DNA testing on some of the clothing JonBenet was wearing the night she was killed.

"Touch DNA are skin cells that you shed when you come into contact with anything," Williamson explained.

Williamson personally selected both sides of the waistband of the child's long johns "so logically where would someone's hands be if they were pulling down someone's pants. So that's where we targeted, where we thought someone would've contacted the long johns."

The results caught everyone off guard.

Williamson told CNN the unknown male DNA originally found in the crotch of JonBenet's underpants matched or "was consistent" with the unknown male DNA that was found on the waistband of the long johns.

"We were, like, this is pretty big. This gives more weight to the theory that this is from the perpetrator and not from manufacturing contamination."

That DNA finding led Mary Lacy, the Boulder district attorney at the time, to make one of the most controversial decisions in the case.

In 2008, she issued an apology to John and Patsy Ramsey, at the same time saying they were exonerated of any criminal wrongdoing in the death of their daughter.

Garnett, although respecting his predecessor, told CNN, "I disagreed that an exoneration on the state of that evidence at that time was appropriate.

"Our role is to bring cases when we are convinced that there is admissible evidence sufficient to convict a particular defendant beyond a reasonable doubt. We are certainly not tasked with exonerating people, since everybody is presumed innocent anyway."

Unresolved questions

Questions and theories over the last 20 years continue, within the community of Boulder and also with the nation at large. Former investigators and experts continue to spur speculation on what really happened -- who killed JonBenet and who still may have knowledge on the case but has not stepped forward.

Garnett says the death is an open case, and his office continues to pursue justice.

"Our question on every case is, 'Do I have evidence of a specific charge against a specific person that is admissible in court and gives me a reasonable likelihood of getting a verdict of guilty beyond a reasonable doubt?' If we get that evidence against anyone and we're convinced we have that after careful review, we will file charges."

Patsy Ramsey died of cancer in 2006. John Ramsey is now remarried, lives his life in the Western United States and says not a day goes by that he doesn't think about JonBenet. He has his favorite picture of her displayed in his living room. He says it is a constant reminder that his priority in life continues to be finding who killed his daughter.

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