JonBenet Ramsey's brother Burke points the finger at the person he believes murdered his sister.

The mysterious murder of six-year-old Colorado beauty queen JonBenet Ramsey is yet to be solved despite almost 20 years passing since her body was discovered.

A new investigation into the death is revisiting the evidence to give viewers new insight into what really happened that night. JonBenet’s father John and brother Burke Ramsey have also appeared in a three-part interview series hosted by American talk show host Dr. Phil.

The initial response to the series focused on the strange demeanor of Burke and the smile that appeared to be on his face when he recalled the day his sister went missing. In the first installment that aired on Monday, Burke discussed who he believes committed the crime against his sister.

The 29-year-old software engineer told Dr Phil he believed the true killer was a sexual deviant who broke in the Ramsey family home.

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

The comments came after Burke denied the allegation he was the killer.

“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.”

The parents of JonBenet - John and Patsy - were ruled out by police in 2008 of any wrongdoing. Burke also commented on the focus the public has formed around the hypothetical involvement of the family.

"It blows my mind. What more evidence do you need that we didn't do it?" he questioned.

The interview series comes alongside the airing of a new documentary series The Case Of: JonBenet Ramsey. The first episode of the series focused on the vital clues of the 911 call, the ransom note said to be left behind and the Ramsey family's behaviour.

You can read our recap of the first episode here.