Justice by Netflix? Fears that TV hit of the year Making A Murderer could lead to the freeing of a man who may be a killer

• Steven Avery's murder conviction the subject of hit Netflix documentary
• He was jailed for murdering photographer Teresa Halbach in 2005
• Nephew Brendan Dassey also convicted but ruling since overturned
• Wisconsin police were found to have 'coerced a confession' from him
• Avery previously wrongly convicted of rape and could have a retrial 

It is a gripping crime drama that has left millions on the edge of their seats, thanks not just to the sensational twists and turns of the plot, but because it is based on a bloody series of events which are all too real.

Making A Murderer, a ten-part series, became a global word-of-mouth phenomenon as soon as it aired on Netflix last December. 

Armchair detectives binge-watched as they followed the fortunes of two convicted killers in a saga more far-fetched than anything a Hollywood screenwriter could conjure up.

The show told how one man spent 18 years in jail for a rape he did not commit, only to be arrested along with his nephew for a still more terrible crime – just weeks after he filed a £27 million wrongful imprisonment case against police and prosecutors.

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Now comes another extraordinary twist, which calls into question both the failures of American courts, and the newfound power of reality TV to influence our lives and institutions – perhaps extending its reach to justice itself.

Late on Friday night, a judge overturned the conviction of the nephew, Brendan Dassey, damning the police for making ‘false promises’ and coercing a confession from a mentally challenged 16-year-old. 

In one pathetic scene, viewers of the show had seen footage of officers pressuring Dassey, who has a mental age of nine, into a making a ‘confession’. 

He then asks if he can leave to do his homework. 

The boy was also shown being bullied and manipulated by his own defence team. 

American prosecutors now have 90 days to decide whether to stage a retrial or release him. 

‘This is right, this is justice,’ his lawyer Laura Nirider said last night, adding that Dassey’s family are ‘grateful, in shock’.

The ruling could also mean that Steven Avery, 54, who is serving life without the possibility of parole for the 2005 murder of photographer Teresa Halbach, stands a chance of winning his fight for a new trial, and may even walk free… all as the cameras roll for a second series of the hit show, which will air at Christmas.

Most will have welcomed this scrutiny of America’s criminal justice system, with its conviction rate above 90 per cent, where the falsely imprisoned can end up languishing for decades without an adequate appeal.

The plight of Dassey and Avery, who are now household names, has attracted high-profile supporters including actors Susan Sarandon, Ricky Gervais and Mia Farrow.

More than 250,000 people signed a petition begging Barack Obama to pardon the two men, which ended up forcing the White House to release a statement – pointing out that the President was not lawfully able to overturn the convictions.

Rallies were also held across the world, including London, Sydney and New York, protesting the two men’s innocence.

Yet there is also considerable evidence ranged against Avery, and some commentators now wonder – should he be released – just how much the decision will have been prompted by the mesmeric power of TV drama and mob sentiment.

Avery was a petty criminal from rural Wisconsin, whose record included robbery and setting fire to the family cat. 

Jogger Penny Beernsten was sexually assaulted in 1985 as she ran alongside Lake Michigan, only a few miles from Avery’s mobile home and car scrap metal yard.

Despite multiple eyewitnesses placing him miles away from the scene, Beernsten picked out Avery from an identity parade, and he was convicted and sentenced to 32 years.

His lawyers claim that a feud between Avery and his cousin – who is married to a local police officer – had led to him being immediately framed for the rape by the Manitowoc County Sheriff’s department.

Filmmakers Laura Ricciardi and Moira Demos were initially drawn to the story after the Innocence Project, a group which has helped overturn dozens of wrongful convictions, began to champion the case.

The first hour of Making A Murderer shows how police and prosecutors rushed to judgment in the rape case – before modern DNA testing exonerated Avery.

Viewers then saw a jubilant Avery walking free from jail after 18 years. 

It might have ended as simply another case of a wrongfully imprisoned man set free but within days Avery had announced he was launching a £27 million lawsuit against police and prosecutors.

He was then charged with the 2005 murder of Teresa Halbach, a 25-year-old who was last seen heading to take pictures of a vehicle at Avery’s yard for a car magazine.

The story is told through police interrogations, recorded prison phone calls, interviews with family and lawyers and courtroom footage. There is no narrator.

While police were convinced that they had the right man – Halbach’s burned remains had been found in a fire pit on Avery’s property, and her car keys were discovered inside his mobile home – many believed he had, yet again, been framed.

Avery’s blood was found inside Halbach’s car, but then a vial of his blood from the previous case was found to have been tampered with.

The box in which it had been stored had the taped lid removed and a tiny needle mark was found in the top of the vial, suggesting blood could have been removed via a syringe and ‘planted’ at the murder scene.

Others questioned why no evidence of rape or the murder had been found in Avery’s home, and why the key to Halbach’s car had been discovered ‘in plain sight’ during the sixth search of the house by officers. 

And why had some of her bones been found at another location well away from Avery’s land?

Manitowoc police officers, who at the time were in the middle of being deposed in his wrongful imprisonment lawsuit, had been involved in gathering evidence in the murder case, and defence lawyers insisted they might have planted evidence to frame him.

It was, however, the ‘confession’ by Avery’s then 16-year-old nephew Dassey which proved the most damning. 

The youngster who was ‘deeply impressionable’, confessed that he raped Halbach and saw his uncle shoot her dead. 

He also admitted helping dismember and burn the body.

Dassey immediately recanted his confession, but it was too late. 

He was convicted of first-degree intentional homicide, second-degree sexual assault, and mutilation of a corpse. Avery was tried and convicted separately.

In a letter written after his 2007 conviction, Dassey said: ‘The investigators tormented me until I said what they wanted me to say. 

'The investigators got into my head saying that if I confessed they would let me go, but when I did they locked me up. They tricked me. I was afraid of them back then.’

He called the trial a ‘witch hunt’ and added: ‘The prosecutors don’t care what they do. They just want a conviction.’

In his ruling on Friday, Milwaukee judge William Duffin ordered Dassey, now 26, to be freed within 90 days unless prosecutors decide to retry him. 

Judge Duffin said that investigators made false promises to Dassey by assuring him ‘he had nothing to worry about’.

‘These repeated false promises, when considered in conjunction with all relevant factors, most especially Dassey’s age, intellectual deficits, and the absence of a supportive adult, rendered Dassey’s confession involuntary under the 5th and 14th Amendments [of the US Constitution],’ he wrote.

The show made unlikely celebrities of some of the main characters. 

Avery’s middle-aged defence lawyers, Dean Strang and Jerry Buting, became internet pin-ups, receiving scores of marriage proposals from adoring women.

Buting has even secured a deal with publishing giant HarperCollins for a book about the case.

While Netflix does not release its ratings figures, Forbes magazine called the show ‘the best documentary ever’, and one critic raved that ‘Making A Murderer is dense with detail and characters and twists and turns that leave the viewer so gripped that sleep and meals become secondary considerations to the business of guzzling every episode’.

Not everyone is a fan, however – particularly those concerned by the ever-increasing reach of television and, in particular, the internet, where debate has been raging.

Many have complained that Making A Murderer is unfairly sympathetic to Avery and Dassey, and leaves out vital evidence which points to their guilt.

Ken Kratz, who originally prosecuted the two men, is writing his own book about the crime – saying that he wants to give a voice to the largely ‘forgotten’ victim.

Kratz, whose reputation was tarnished by a 2014 sexting scandal, complained: ‘Any time you include only the statements or pieces of evidence that support your particular conclusion, then that conclusion could be reached. It really presents misinformation.’

He claimed that vital evidence –including the fact that Avery called Halbach’s work and specifically asked for the young, female photographer on the day of her murder – was left out of the show.

Halbach had previously taken pictures of Avery’s cars and, according to Kratz, ‘she was creeped out by him.

She went to her employer and said she would not go back because she was scared of him’.

Even Avery’s son Steven Jr is unsure of his father’s innocence. Last month he revealed that he had ‘no idea’ if his father was guilty, saying: ‘The only thing I know was the entire case was very shady.’

He added: ‘It’s clear that there was corruption. Him and Brendan deserve a fair trial. If they’re guilty, then let them sit.’

So far neither Avery nor Dassey have seen the show, but they can only be grateful for the attention it has brought.

Avery’s lawyer Kathleen Zellner said last night that she had been visiting her client in prison when the news that his nephew’s conviction had been overturned came through. She said he was ‘thrilled’.

‘We know when an unbiased court reviews all of the new evidence we have, Steven will have his conviction overturned as well,’ Zellner said, claiming that new developments in scientific testing since Avery’s 2007 conviction will ‘almost certainly’ clear him.

She told America’s NBC network: ‘Am I going to tell you exactly what it is? I am not. But it’s been a long time.

‘There was a lot of evidence that wasn’t tested.’

Filmmaker Laura Ricciardi promised more bombshells, including an interview with a juror who convicted Avery for murder, but who had felt ‘bullied’.

She explained: ‘The juror contacted us directly and told us the verdicts in Steven’s trial were a compromise. 

'They were afraid if they held out for a mistrial that it would be easy to identify which juror had done that and they were fearful for their own safety.’

Whatever twists and turns the case takes next, one thing is for sure: the cameras will be rolling to satisfy the appetite of millions of true-crime fans.

But at what long-term cost, it is harder to say.