It has been nearly 30 years since child beauty pageant queen JonBenet Ramsey was found murdered in her Boulder, Colorado, home on Dec. 26, 1996, and the case remains unsolved to this day.

A new special documentary on the cold case aired in the United Kingdom this week that reviewed the known facts of the case and looked at some of the different suspects who've been viewed as responsible for the six-year-old JonBenet's death almost three decades ago, according to the UK's iNews.

That is seemingly good news for the slain girl's father, John Ramsey, who has been attempting to raise awareness about the unsolved case and press law enforcement to address his unanswered questions, particularly about purportedly untested DNA evidence.

Questions remain about JonBenet's death

The new special, titled "Who Killed JonBenet Ramsey? A Suburban Nightmare," aired Thursday night on the U.K.'s Channel 5, according to MemorableTV.

"The film provides unprecedented access and includes cooperation from John Ramsey, JonBenét’s father," the outlet noted. "John, finally cleared as a suspect, persistently urges the Boulder Police Department to re-examine and release key pieces of physical evidence. He believes that this evidence may hold crucial answers that could lead to the identification of his daughter’s killer."

iNews noted that John and Patsy Ramsey, JonBenet's mother who died of ovarian cancer in 2006, found an alleged ransom note in their kitchen on the morning after Christmas and reported their daughter missing to the police, only to find her dead body a few hours later in the basement.

An autopsy revealed that the little girl had been strangled to death but had also suffered a skull fracture and appeared to have been sexually assaulted. Various pieces of evidence were recovered from the scene, including unknown DNA samples, and a still-open investigation was launched into the murder.

Her family was once suspected

The new special about JonBenet Ramsey also looked at what was known of the few suspects in the case, including the girl's parents and older brother Burke, who was nine years old at the time.

Though the family was indicted by a grand jury a few years after the murder -- notably for child endangerment and obstruction, but not the murder -- those charges were ultimately dropped by prosecutors due to a lack of evidence.

Indeed, a thorough review of the evidence, including DNA and the ransom note's handwriting, led to the parents and brother eventually being exonerated of any wrongdoing in the incident.

Other possible suspects in the murder

There were two other notable suspects in the case, though, the first being a former school teacher named John Mark Karr, who confessed to the crime and was arrested in Thailand in 2006.

He claimed to have drugged and sexually assaulted and accidentally killed the little girl, but no drugs were found in JonBenet's system and his DNA did not match samples from the scene. Further, his confession only included publicly known information, and his confession was eventually dismissed as false.

The other main suspect, a convicted sex offender named Gary Oliva who was just released from prison this year after serving time for child pornography, is alleged to have confessed to the murder to a friend at the time and years later in letters from prison.

Oliva, who'd been previously jailed for sexually assaulting a young girl in Oregon as well as for attempting to strangle his mother to death, was a homeless drifter in Boulder at the time of JonBenet's death, was found in possession of a photograph of her years later, and his handwriting appears to match that of the ransom note.