During a sitdown in advance of the Dr. Phil season 15 premiere, the host reveals that he asks Burke Ramsey, who was nine when his sister JonBenet Ramsey was murdered, whether he was responsible for the crime.
"I know people think I did it; that my parents did it," Burke told Dr. Phil. "I know that we were suspects."
WATCH: JonBenet Ramsey's Brother Speaks Out on Sister's Unsolved Murder Nearly 20 Years After Her Death
The case is one of the most talked about unsolved mysteries in American history. JonBenet, a 6-year-old child pageant star, was found dead in the basement of her family's Colorado home on Dec. 26, 1996. At the time, her parents, John and Patsy Ramsey, made the initial call to police and said they found a note demanding $118,000 in ransom for their daughter. John Ramsey later found his daughter's body hours after police completed a search of the home. John and Patsy (who died in 2006 after a battle with ovarian cancer) were primary suspects for more than a decade until police cleared them of any wrongdoing in 2008. Burke was also cleared by police.
Burke, now 29, has never spoken publicly about the incident until now.
"The first thing I remember was my mom bursting in my room frantic, saying, 'Oh my gosh!' running around my room, looking for JonBenet," Burke told Dr. Phil. "The next thing I remember was a police officer coming to my room and shining a flashlight."
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While the magnitude of his family's situation might not have occurred to him at first, the media attention eventually made Burke realize that his life would never be the same.
"It's hard to miss cameras and news trucks in your front yard," Burke said. "We'd go to the supermarket sometimes and there'd be a tabloid with JonBenet's picture plastered on the front. It just made me a very private person."
As the 20th anniversary of JonBenet's tragic death approaches, Burke was aware that the crime would once again be the subject of many headlines, which is why he chose to finally give an on-camera account of his side of the story.
"His thinking was, 'If that's going to happen, I want to control the narrative,'" Dr. Phil says.
And Dr. Phil didn't pull any punches.
WATCH: Intense First Trailer for 'The Case of: JonBenet Ramsey' Debuts
"I asked him straight up, 'Did you murder JonBenet, your sister?" Dr. Phil tells ET.
Find out Burke's response when the three-part season 15 premiere of Dr. Phil -- which will also air never-before-seen interrogation interviews conducted with Burke when he was 9 and 12 years old -- kicks off Monday, Sept. 12.