Leading criminal experts believe they finally know who killed JonBenét Ramsey.

Two decades on from the murder of six-year-old beauty queen JonBenét Ramsey, a group of the world’s top investigators say they finally know who the killer is.

Revisiting the crime in a new two-part series, The Case of: JonBenét Ramsey, the investigators considered a number of crime scene possibilities, ultimately concluding that the most likely killer was JonBenét’s older brother, Burke Ramsey.

Jim Clemente, Laura Richards and Dr Werner Spitz. Source: Channel 9.

In episode one, the experts looked at the cause of death, ransom note and immediate moments following the murder.

In episode two, however, the team dedicated their time to looking at who could have committed the crime, inconsistencies in the crime scene and event accounts, the experiences of the investigators who originally worked on the case, and alleged DNA evidence, all of which eventually lead to the conclusion that Burke Ramsey was the most likely to have committed the crime, with his parents Patsy and John then covering up the "accidental murder" for their son.

Burke and JonBenet Ramsey. Source: Channel 9.

James Kolar, the former chief investigator for the District Attorney in the Ramsey's home city of Boulder, Colorado presented the damning theory of JonBenét's final moments, with the documentary's primary group agreeing strongly.

This group included behavioural analysts Jim Clemente and Laura Richards, linguistics profiler Jim Fitzgerald, statement analyst Stan Burke, forensic scientist Dr Henry Lee, forensic pathologist Dr Werner Spitz.

Setting out a timeline of events that begin the evening before, Kolar began, "My hypothesis was that I think the Ramseys came home at around 9.30, 10 o'clock."

JonBenet Ramsey. Source: Channel 9.

"I think JonBenet was asleep. I think John did carry her upstairs, Patsy remained downstairs with Burke and served him the tea and the pineapple," he said.

"I think that accounts for the physical evidence as well as the latent print. Then she [Patsy] got JonBenet up to make sure she used the toilet, so she didn't wet the bed that night," he continued.

"I think that accounts for the physical evidence as well as the latent print. Then she [Patsy] got JonBenet up to make sure she used the toilet, so she didn't wet the bed that night," he continued.

Experts say they now know who killed JonBenet Ramsey. Post continues... 

While taking JonBenét to the bathroom, Kolar says he believes Patsy then left Burke with a bowl of pineapple and some tea. After putting her back to bed, Patsy then went to her bedroom to pack for an upcoming trip.

Now awake from being taken to the bathroom, Kolar believes JonBenét then snuck downstairs and attempted to eat some of Burke's pineapple. He believes this was when the then nine-year-old lost his temper and struck his younger sister with a blunt object - most likely a Mac flashlight found on a nearby bench - which the experts discovered to be the cause of death in episode one.

The documentary's team of key investigators. Source: Channel 9.

Despite the theory, Burke Ramsay, who is now 29, has maintained his innocence.

Speaking to Dr Phil as part of a three-part anniversary special on the death of his sister, Burke says he believes a paedophile killed his sister.

"I kinda always just thought it was a paedophile, who saw her at one of the pageants, snuck in, who knows?" Burke said.

Burke Ramsey on Dr Phil. Source: Channel 9.

On the topic of being accused as the killer, he said, “I don't know what to say to that because I know that's not what happened. There's been people who have said that's not even physically possible for a nine-year-old to do that,” he said.

“Like, you won't find any evidence because I didn't do it.”

Part II of The Case of: JonBenét Ramsey airs on Channel 9 on Tuesday at 8.40pm. 

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