One of the grand jurors who viewed evidence related to JonBenet's murder refused to say who he believes killed the six-year-old beauty queen - after bragging he 'highly suspects' he knows the identity of the killer.

The man testified anonymously on Friday night's episode of 20/20 on ABC, which took a look back at the case 20 years afterwards. He was part of the jury that voted to indict JonBenet's parents John and Patsy on charges related to the murder of their daughter after a year-long grand jury trial.

The district attorney nullified the findings of his grand jury and declared there wasn't sufficient evidence to indict the little girl's parents. Friday night's juror, however, said he believed John and Patsy should have been tried, based on the evidence he had seen.

But the man told host Amy Robach there would have been no way for a jury to find the parents guilty. He then said he had a strong feeling he knows who killed JonBenet - but copped out when Robach asked for a name.

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A grand juror who worked on the JonBenet Ramsey case 20 years ago testified anonymously on Friday night's episode of 20/20 on ABC (pictured)

The man said he 'highly suspects' he knows who killed the six-year-old pageant queen (pictured) on Christmas night 1996 - but refused to name names

Friday night's grand juror believes JonBenet's parents John and Patsy (pictured) should have been indicted on charges related to their daughter's murder - but believes it would have been impossible for a jury to find them guilty

Infuriated viewers expressed their disappointment on Twitter after the grand juror refused to say who he believed killed JonBenet

'I wish not to answer that question,' the man said, infuriating viewers who had sat through the rest of the episode eager to hear the big reveal.

The grand juror did say he believed Patsy and John should have been indicted on charges related to their daughter's murder. When asked if he believed that John and Patsy should have been tried, he said: 'Based on the evidence that was presented I believe that is correct.'

When asked however if he thought that the district attorney would have been able to get a jury to find the parents guilty, he said: 'There is no way that I would have been able to say, "Beyond a reasonable doubt, this is the person."'

He then added: 'And if you are the district attorney, if you know that going in, it’s a waste of taxpayer dollars to do it.'

Robach then asked the juror if he knew who murdered the young girl after the evidence that was presented to the grand jury.

'I highly suspect I do,' said the juror.

He also spoke about the trip the grand jury members took to the Ramsey home, and being in the basement where the young girl's body was found by her own father, just hours after she was reported as missing to police.

'In the basement where she was found, it was actually kind of an obscure layout. You come down the stairwell and you had to go into another room to find a door that was closed. It was a very eerie feeling. It was like, "Somebody had been killed here,"' said the juror.

John and Patty Ramsey (pictured in the 1990s with their children Burke and JonBenet) were never formally indicted because the DA refused to sign the documents

The grand jury voted to indict the Ramseys on four counts but they were never formerly indicted. Patsy's child abuse indictment is pictured

The accessory charge declared that the two 'did unlawfully, knowingly and feloniously render assistance to a person, with intent to hinder, delay and prevent the discovery, detention, apprehension, prosecution, conviction and punishment of such person for the commission of a crime'

A handwriting expert who examined the ransom note left in the case said on Friday night's episode it is very likely that the letter was written by the child beauty queen's mother Patsy.

'It's highly probable that she wrote the ransom note,' handwriting expert Cina Wong said.

Wong spent three weeks examining the note and comparing it to 100 examples of Patsy's handwriting back in 2000, and found multiple similarities between the two.

For instance, the ransom note had the letter 'A' written in four different variations, and Patsy wrote that same letter in those some four ways.

In total, Wong found more than 200 similarities in the writing of the ransom note and the 100 samples of Patsy's penmanship.

Handwriting expert Cina Wong said during the episode that it is 'highly probable' that JonBenet's ransom note was written by her mother Patsy (samples of the ransom note on left and Patsy's handwriting on the right)

In total, Wong found more than 200 similarities in the writing of the ransom note and the 100 samples of Patsy's penmanship she examined

Wong (above) spent three weeks examining the note and comparing it to 100 examples of Patsy's handwriting back in 2000

Friday's episode featured archive footage of the investigation and excerpts of home videos, showing the Ramsey family in happier times.

Patsy had just recovered from ovarian cancer when JonBenet died. The family, originally from Atlanta, was 'high society' for Boulder, according to the segment.

The episode included footage from an interview given by Patsy and John on CNN just five days after the murder.

'As a mother my heart went out to this couple, but my journalistic brain said to me "This isn’t right, they should be talking to the police, not to the public," ' investigative reporter Diane Dimond said on Friday's show.

John later said they had done the interview reluctantly, pressed by their friends who didn't want JonBenet's parents to be painted as guilty.

In the end, the grand jury voted to indict the Ramseys on four counts but they were never formerly indicted because the DA refused to sign the documents.

The grand jury planned to indict John and Patsy for child abuse resulting in death and accessory to a crime.

The child abuse charge stated that John and Patsy 'did unlawfully, knowingly, recklessly and feloniously permit a child to be unreasonably placed in a situation which posed a threat of injury to the child's life or health, which resulted in the death of JonBenet Ramsey, a child under the age of sixteen'.

The accessory charge declared that the two 'did unlawfully, knowingly and feloniously render assistance to a person, with intent to hinder, delay and prevent the discovery, detention, apprehension, prosecution, conviction and punishment of such person for the commission of a crime, knowing the person being assisted has committed and was suspected of the crime of Murder In the First Degree And Child Abuse Resulting In Death.'

Boulder police and prosecutors are now planning a new round of testing on DNA evidence found in the case.

The tests would also tap into an FBI database that includes genetic profiles from more than 15.1 million known offenders.

Garnett and Boulder police Chief Greg Testa said that they have already discussed the matter with the Colorado Bureau of Investigation during a meeting just before Thanksgiving.

The body of JonBenet was found bludgeoned and strangled hours after she was reported missing and covered by a white blanket with a nylon cord around her neck, her wrists bound above her head and her mouth covered by duct tape.

Her skull was also cracked.

John and Patsy had called the police to report her kidnapping and said they found a note demanding a ransom of $118,000 for her safe return - and that they had not contact the authorities.

Despite this, police arrived to their home shortly after in clearly marked vehicles.

John and Patsy would remain the primary suspects in their daughter's death for more than a decade, and it was not until 2008 that police finally cleared them of any wrongdoing.

At that time, Patsy had been dead for two years after a lengthy battle with ovarian cancer.

No one in the family was ever charged in the death of the six-year-old, but for years tabloids and members of the public believed they were the culprits of this unspeakable crime.

Most of these stories focused on parents John and Patsy, but some went so far as to claim that Burke had been responsible for his sister's death - despite the fact that he was only nine years old at the time.

Appearing on Barbara Walters Presents American Scandals, John said that he and his late-wife Patsy did everything they could to protect their son Burke from learning that he was being accused of murdering his sister.

'We tried to shield him from that,' John said of the tabloid reports about Burke.

'Friends would ask us, "What can we do to help?" We said, "Next time you go in the supermarket, call the manager over when you see our child’s photo on the front cover, and ask him to remove it." A lot of them did that.'

The body of JonBenet was found bludgeoned and strangled hours after she was reported missing and covered by a white blanket with a nylon cord around her neck, her wrists bound above her head and her mouth covered by duct tape

Scene: The grand jury member said he got a 'very eerie feeling' when he saw the basement of the Ramsey home (pictured), which the jury visited

Stories would point to the fact that Burke was in the house when JonBenet was reported missing, but his parents always stood firm on the fact that he was sleeping the entire time and did not wake up until after they called police.

He was exonerated by DNA evidence in May of 1999, a little more than two years after the murder.

Burke, who is now 28-years-old, has mostly avoided the public spotlight since his sister's death.

John also said that he still believes the killer will be found.

'I think we will have two ways that will happen,' John told Walters in their interview.

'It will either be a DNA match or someone who knows something will become angry or bitter against this person and will tell.'

Male DNA was found on the underwear of JonBenet when her body was discovered, but authorities have never been able to match it to a suspect.

There was also a bowl of pineapple found in the kitchen when the young girl was first reported missing but police on the scene allowed someone to clean the bowl.

This ended up being a crucial error as JonBenet was found with pineapple in her stomach when her body was examined by the coroner.

The house was not sealed off by police and friends and family were allowed to come and go during the initial investigation, contaminating the crime scene.

Another look: Boulder police and the district attorney recently said that they will be retesting the DNA evidence in the case (John and Patsy are pictured in 1996)

Keeping quiet: JonBenet's brother Burke (pictured above at his mother's funeral) recently spoke about the murder

John - who was briefly linked to Natalee Holloway's mother Beth in 2007 and remarried in 2011 to Jan Rousseaux - also discussed how he lost his millions after the death of JonBenet when he decided to move the family out of Boulder and back to Atlanta, not realizing the stigma that would be placed on him by the public and how difficult that would make it for him to obtain a job.

'I was told by a very experienced FBI person that most victims of violent crime end up broke,' said John.

'It's very expensive to deal with the justice system. You make bad decisions - you sell your home, you quit your job, you move, you change jobs.'

In addition to losing JonBenet, John had also lost his oldest daughter from a previous marriage in 1992. Elizabeth was 22-years-old when she died in a car accident.

As a result of what he has gone through, he now has advice for others who might face a similarly tragic situation.

'When something really tragic happens in your life, put your life in park. Give your checkbook to a trusted friend. Avoid making any big decisions,' said John.

'Because you're just not capable of making good decisions.'