It’s been almost 30 years since six-year-old beauty pageant queen JonBenét Ramsey was found dead in the basement of her family home on Boxing Day in 1996. The case gripped the world, with Ramsey’s parents, John and Patsy, subject to speculation in the media that they were somehow complicit. However, no one has ever been charged with her murder.

Enter Netflix. In a new three-part documentary, Cold Case: Who Killed JonBenét Ramsey?, Oscar-nominated director Joe Berlinger re-examines the infamous case and hopes to flip the script. ‘I think the Ramseys have been perhaps the most mistreated people in American history by both the police and the media,’ Berlinger tells Grazia. ‘I believe that they’re innocent. If you really look at the facts of the case, it’s absurd [to think] that the parents had anything to do with the crime.’

The series exposes the gross mishandling of the case both at the time and since – a contaminated crime scene, defective DNA sampling, salacious and biased reporting to frame the family, with wild conspiracy theories shared online in recent years and a string of inadequate detectives investigating. The Ramseys, while never charged, were ostracised by their community and sentenced in the court of public opinion.

The only Boulder police officer in the house when John discovered his daughter’s body in the basement, Linda Arndt, later went on national television to explicitly accuse him of murder. ‘I know who killed JonBenét,’ she told ABC News. ‘There’s no doubt in my mind who killed JonBenét.’ Her explanation was that John had ‘a look in his eyes’ and went to search the basement too quickly. John reflects on the significance of this interview in the documentary and says, ‘that’s how it got started.’

By 2000, the former leading detective on the case, Steve Thomas, published a well-received book called JonBenét: Inside the Ramsey Murder Investigation where he accuses Patsy of her daughter’s murder.  It was hailed as ‘thorough’ and ‘holding a treasure trove of facts’ by reviewers.

Berlinger admits he ‘fell for all the hype’ at the time, as the father of a then two-year-old girl. ‘Often, incompetent or inexperienced police lock into an initial theory, because there’s pressure to solve a crime and they have tunnel vision,’ he says. ‘Years later, I was introduced to the work of Lou Smit and realised it’s the opposite that’s true.’

Detective Andrew ‘Lou’ Smit worked on the case at the time but resigned after he concluded that the Ramseys were not responsible and that Boulder Police Department had, he believed, been unjustifiably pursuing them. The series also features journalist and political commentator Michael Tracey, who claims he secured a recorded confession from one of the other suspects following his own investigative reporting.

The agenda of the documentary is clear: to reopen one of the biggest cold cases in history. Berlinger thinks it is a crime that can still be solved. ‘There are certain items that need to be re-tested because DNA technology has advanced. There are certain items that weren’t ever tested and there’s a very specific test that needs to be done regarding unidentified male DNA that was found in [JonBenét’s] underpants.’

For the family of JonBenét, it may already be too late. Her father, now 80, has lived much of his life under a cloud of perceived culpability. Patsy died from ovarian cancer in June 2006 without ever seeing anyone convicted for her daughter’s murder. And JonBenét’s older brother, Burke, who was nine and at home when she died, has also been subject to irresponsible media reports, Reddit sleuths and various conspiracy theories that name him as the killer. One wild but widely reported theory at the time was that Burke strangled his sister because she ‘ate some of his snack’. He declined to feature in the series.

It’s easy, in these instances, to see how a curious public pieced together the so-called evidence they were presented with and reached a presumptuous conclusion. It’s also easy to see how that can, and perhaps has, perverted the course of justice.

In a streaming landscape occupied by insatiable true crime fans, there’s no doubt that Netflix’s latest offering will be another hit. We saw the real-life impact that can have with Monsters – the dramatised true crime series about Lyle and Eric Menendez, who were sentenced to life imprisonment for the first-degree murder of their parents in 1996 – when, in October this year, Los Angeles County District Attorney George Gascon recommended that the brothers be re-sentenced and made eligible for parole.

All of which poses the question: is being the subject of a hit Netflix documentary your only chance at justice? Berlinger certainly hopes that his documentary series – which he believes is the ‘most comprehensive’ offering on the case to date – will achieve just that. ‘For me, the reason to do this is to try to give this family some peace, both in getting something responsible out into the media about the case and, more importantly, to apply pressure to get the authorities to finally right this terrible wrong.’

Stream Cold Case: Who Killed JonBenét Ramsey? on Netflix from 25 November.