The mother of Making a Murderer’s Brendan Dassey has called the chief prosecutor in her son's case ‘a piece of dog s**t’ in an exclusive interview for a tell-all book, provided to DailyMail.com by the author.

The hit Netflix series Making a Murderer, released in 2015, analyzed the case of Wisconsin man Steven Avery, now 54, and his nephew Brendan Dassey, now 27. The duo were sentenced to life in prison in 2007 during separate trials for the murder of 25-year-old photographer Teresa Halbach; Avery was given no chance of parole.

The documentary set out to prove that the investigation led by local law enforcement was flawed, and that Dassey and Avery are innocent.

Dassey had his original life sentence quashed by Judge William Duffin last August, after his Dassey's lawyers claimed investigators tricked him into a confession. That ruling is currently under appeal by Wisconsin state and Dassey remain in prison.

Now, prison rights activist Shaun Attwood has done his own investigation of the case and was given unprecedented access to the Avery and Dassey families for his book, ‘Un-making a Murderer: The Framing of Steven Avery and Brendan Dassey.'

Barbara Tadych (left), the mother of Making a Murderer’s Brendan Dassey, above, has called the chief prosecutor in her son's case ‘a piece of dog s**t’ in an exclusive interview for a tell-all book, provided to DailyMail.com by the author. Pictured, Tadych and her son and a friend during a recent prison visit

Dassey (pictured during his trial in 2007) had his original conviction quashed by Judge William Duffin last August, who said investigators tricked him into a confession, but that ruling is currently being appealed by Wisconsin state and Dassey currently remain in prison

The hit Netflix series Making a Murderer, released in 2015, analyzed the case of Wisconsin man Steven Avery, now 54, (pictured in 2005) and his nephew Dassey, now 27

It comes on the eve of prosecutor Ken Kratz’s opposing book, allegedly proving Dassey and Steven Avery did commit Halbach's murder.

In an exclusive interview for 'Un-making a Murderer,' Brendan Dassey's mother Barbara Tadych spoke for the first time about her dislike of Kratz and her son's interrogation by police without her present - even though he was 16 years old at the time, had an IQ of 90 and the mental age of nine.

In the book, Tadych doesn’t hold back on her views about the three men responsible for finding Avery and Dassey guilty: former Wisconsin Calumet County district attorney Ken Kratz and chief interrogators Mark Wiegert and Tom Fassbender.

The duo were sentenced to life in prison in 2007 for the murder of 25-year-old photographer Teresa Halbach

She’s also highly critical of Dassey’s original defense attorney Len Kachinsky, who was a court-appointed attorney accused of working alongside the prosecution, with his ‘misconduct’ branded ‘indefensible’ by Judge Duffin.

She says that Dassey’s interrogators were so forceful, they even tried to get her to claim that her own brother Steve Avery had sexually abused her.

‘Wiegert and Fassbender are [deleted] that take innocent people and lie to them and get them to say what they want them to say,' she said.

'Wiegert always said to me that every family has a black sheep in it. Fassbender and [Calumet County Deputy] Wendy Baldwin tried to get me to say bad things about my brother, Steve: that he had sexually molested me.”

‘My thoughts on Ken Kratz are not good. He is a piece of dog s**t. Oh no! That was too good for him!

'I think they should put all of them in prison for what they did to us, including Len Kachinsky [Dassey’s defense attorney], who is not any better than the rest of them. He is a lying d*****bag.’

In an exclusive interview for 'Un-making a Murderer,' Dassey's mother Barbara Tadych spoke for the first time about her son's interrogation by police (left in 2006) without her present - even though he was 16 years old at the time, had an IQ of 90 and the mental age of nine

'I think they should put all of them in prison for what they did to us, including Len Kachinsky [Dassey’s defense attorney], who is not any better than the rest of them. He is a lying d*****bag,' Tadych said. Pictured, Dassey in 2010, listening to Kachinsky's testimony

Tadych says that Dassey’s interrogators were so forceful, they even tried to get her to claim that her own brother Avery (pictured in 2007) had sexually abused her

‘Wiegert and Fassbender take innocent people and lie to them and get them to say what they want them to say,' Tadych, here with son Brendan, claims

Kratz's book ‘Avery: The Case Against Steven Avery and What "Making a Murderer" Gets Wrong.' will be published February 21.

The foreword is written by Nancy Grace, the former Atlanta prosecutor turned TV legal analyst and ex-host of HLN.

Kratz, who resigned from his post in 2010 following a scandal in which he allegedly sent sexually explicit text messages to a domestic violence victim, claims that the global hit documentary omits crucial forensic evidence.

In an exclusive interview with DailyMail.com, Kratz claimed that the TV series distorted the facts.

'Making a Murderer is a very good piece of entertainment but it's not really what happened - it's simply not how the case happened in real life. The filmmakers have distorted and misrepresented the case. This isn't what the jury got to see or hear when they decided Mr. Avery was guilty,' Kratz said.

'FISHY' INTERROGATIONS: 'THEY'RE LYING THROUGH THEIR TEETH' Detectives Mark Wiegert and Tom Fassbender interrogated Brendan on three separate occasions on February 27, 2006 - at Mishicot High School, Two Rivers Police Dept and Fox Hills Resort. But Brendan's mother claims that there was also a fourth interrogation that no one knows about because it happened outside. ‘At the cabin in Crivitz, Fassbender took Brendan outside for an interview. There is no record of that anywhere. The day they took me, Blaine and Brendan to Two Rivers’ police station, they told me that I was not allowed in while they interviewed my sons. 'They took them to Fox Hills Resort. I was told if I left I would be arrested. They were not allowed to leave Fox Hills. Wiegert and Fassbender kept saying to me: “It’s your brother or the yard.” ‘If I had been allowed into the interrogation room, I think things would have been way different because they would have never been able to pump things into Brendan’s head like they did. I started to think something was fishy at the Two Rivers Police Department and at Fox Hills when Fassbender and Wiegert said that if I left they would pick me up. ‘They say that I gave them permission to interview Brendan. Well, that was a lie. 'The day they did this at school, I was at work for ten hours. They called me after the fact. They interviewed him for three to four hours, and then first contacted me to come get him. I never gave them permission to do what they did. They did it behind my back. 'And when they took us to the police station, they told me I couldn’t go in with him because he was going to give them a gruesome story that I wouldn’t be able to handle, and told me to go have a seat on the chair. That is the truth, and they are lying through their teeth.’ Advertisement

He went on to give a number of examples of viewers being deceived by the editing technique called splicing, which is taking an answer given in one place and using it to answer another question - or even a question never asked in real life.

He adds: ’The filmmakers did a lot of things like omit things, shuffle things around or only tell you things that support their narrative but when a filmmaker is willing to show trial testimony and tell viewers: 'This is what happened, this is what the jury got to see' and then afterwards you find out it's not, it's unforgivable.’

Along with two police officers involved in the case, Lt. James Lenk and Sgt. Andy Colborn, Kratz says he received death threats and lost his law firm, but now feels someone should ‘stand up’ for the conviction and the maligned officers.

Meanwhile, the Dassey and Avery family business, Avery Salvage Yard - where photographer Halbach's charred teeth and bone fragments were found in 2005 - is on the verge of financial ruin. Carla Chase, Dassey’s cousin, wrote on the family’s official Facebook group that ‘the Avery salvage yard has been hurting for business.’

They’ve now set up a webpage selling Avery Salvage Yard memorabilia including hoodies, t-shirts, caps, mugs and buttons.

Tadych admits that the whole family has been left ‘heartbroken’ by the murder case, but grateful for Making a Murderer.

‘Brendan’s wrongful conviction has taken a toll on all of us. We are heartbroken. We have had counseling for our stress and frustration. Our family has suffered for over 10 years. It hasn’t been easy,’ Barbara said.

‘Brendan’s release, yes, he will probably need counseling for the simple reason to get him reunited with society. Being on the outside, I think he will cope as long as I stand by him until he feels comfortable.

‘It is frustrating and heart-breaking to not have him here for the holidays. Brendan passes his time in prison reading, writing, playing cards and going to the library.

'He makes phone calls, watches TV, listens to the radio and waits for visits from his family. He doesn’t have a job in prison. Brendan’s mental strength comes from us having stuck by him for all these years.

‘Making a Murderer, has done wonders for the family and it has also got the truth out there about the corruption and the liars.

‘Brendan was supposed to have been released in November 2016, but it turned out to be a let-down again from the state and it was very emotional and very heart-breaking again.

Proescutor Ken Kratz (pictured giving his closing argument in 2007), on the other hand, said: 'Making a Murderer is a very good piece of entertainment but it's not really what happened - it's simply not how the case happened in real life. The filmmakers have distorted and misrepresented the case'

‘So this doesn’t happen again to anyone else’s child, I ask people to please sign the petition out there called the Barbara Tadych Law [matching juveniles with an attorney during interrogations], so we can get this passed. And always have someone with you when you are being questioned by the police. Don’t let anyone put words in your mouth that aren’t true. If you didn’t do it, don’t say it.’

At the time of Teresa’s murder, Brendan was a quiet sophomore at Mishicot High School. His interests included Wrestlemania, animals, video games such as Pokémon and books in the mystery, fantasy and Japanese cartoon genres.

Shaun Attwood's book, ‘Un-making a Murderer: The Framing of Steven Avery and Brendan Dassey,' gets unfettered access to Dassey and Avery's families

Dassey wrote to Attwood for his book and said that his favorite wrestler was John Cena and liked to ‘eat hamburgers and chocolate-chip granola bars, preferably washed down with orange juice.’

Attwood knows the prison system well after serving six years - two in Maricopa County Jail, Arizona, dubbed ‘America’s most dangerous prison’ - for dealing ecstasy while making millions on the stock market.

He says reading 1,000 books in prison saved his life and now donates any profit to providing books for schoolchildren. He’ll be splitting the proceedings for his new book between schools and Steven Avery’s legal fees.

Attwood adds: ‘Enduring over a decade of wrongful imprisonment was psychological torment enough for Brendan and his rock of support, his mother, Barb. The announcement of Brendan's release last year snapped them out of ten years of suffering and filled them with high expectations and planning for Brendan's future.

‘Brendan and Barb were delighted that Making a Murderer Series One exposed the lies and corruption, and has brought Brendan to the brink of being freed.

'With the state of Wisconsin closing ranks to protect the players in the framing and to prevent having to pay out millions in compensation, the Dasseys' are hoping that season 2 will provoke a second avalanche of public support that will topple Manitowoc's house of cards.’