A federal judge in Wisconsin, USA, has overturned the murder conviction of Making a Murderer’s Brendan Dassey - and now Steven Avery's lawyer has said that the same is likely to be done for her own client.

Dassey, 26, was found guilty, along with Avery, of murdering freelance photographer Teresa Halbach a decade ago and sentenced to life in prison. 

But, as Making a Murderer fans know, Dassey’s attorneys argued that their client, who was 16 at the time of Halbach’s murder, was coerced by the Manitowoc County Police Department to confess.

Their claims were supported by the fact that Dassey didn’t have a lawyer present when they questioned him.

Now U.S. Magistrate William Duffin has agreed that police used “deceptive tactics” to get the teenager to confess to helping Avery commit murder.

As a result, his conviction has been overturned, with the judge ordering Dassey be freed within 90 days of the ruling.

"This is right, this is justice," his attorney, Laura Nirider, told ABC News.

"We are over the moon. We were notified by email and I read this decision on my phone … 91 pages, unbelievable."

She added that his family is "grateful, in shock, trying to process this."

Dassey’s half-brother, Brad, also took to Facebook to share his joy – although he reminded Making a Murderer fans that the courts maintain the right to appeal the decision for the next 90 days.

He said: "Just hope for the best. We'll all talk as soon as he's for sure OUT. Thank you."

Meanwhile, Avery’s attorney, Kathleen Zellner, has said that she is optimistic about what this development could mean for her own client.

In a statement to Access Hollywood, Zellner, said: "We are thrilled for Brendan Dassey that his conviction has been overturned.

“We fully expected this outcome from an unbiased court that carefully examined his confession.”

She continued: "I was just visiting Steven Avery and he is so happy for Brendan… [and] we know when an unbiased court reviews all of the new evidence we have, Steven will have his conviction overturned as well."

Making a Murderer filmmakers Moira Demos and Laura Ricciardi – who recently announced their plans for a second series - also reacted in a statement.

"Today there was a major development for the subjects in our story and this recent news shows the criminal justice system at work," they said.

"As we have done for the past 10 years, we will continue to document the story as it unfolds, and follow it wherever it may lead."

Avery is currently serving life in prison without parole.

In 1985, Avery was wrongfully imprisoned for sexual assault, false imprisonment and attempted murder – but, in 2003, he was released when advances in DNA technology proved it was another man’s crime.

Just two years later, Avery was re-arrested and charged with the murder of Halbach, who had disappeared after photographing a vehicle at Avery’s salvage yard.

Bloodstains in her car matched Avery’s DNA, although his attorneys later accused police officials at the Manitowoc County Sheriff’s Department of planting false evidence and of having a “conflict of interest” in the investigation.

This, conspiracy theorists have suggested, was due to the fact that officers faced a huge financial penalty over the first case.

As a result, the Netflix crime documentary cast serious doubts over the decisions of the American justice system, with British fans staging a protest outside the US embassy in London to call for Avery and Dassey’s release.

However, since the show’s initial release, a number of articles have appeared online which suggest that filmmakers chose to show Avery in a biased light, leaving out numerous bits of evidence – including extra DNA evidence.

Image: Netflix