Jodi Stachowski, the former fiancee of Making a Murderer‘s Steven Avery, has called him a “monster” who is “guilty” of murdering Teresa Halbach.

Ms Stachowski, who featured heavily in the Netflix documentary, supported Avery in the lead-up to his trial but broke contact with him on the show because of her alcoholism.

However, in a teaser for a CNN interview, Ms Stachowski say she believes Avery is responsible for the murder of the 25-year old photographer – a crime for which he is currently serving life in prison.

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“What do you want the world to know?” asks an interviewer in the video, posted to Twitter.

“What a monster he is. He’s not innocent,” replies Ms Stachowski.

The documentary charts the alleged wrongful incarceration of Avery.

When asked if she was in love with Avery during their two years together, Ms Stachowski responds with: “No.”

“I ate two boxes of rat poison, just so I could get away from him, and ask the hospital to get the police to help me,” she says.

Prior to being charged with the murder he maintains he did not commit, Steven Avery and Ms Stachowski planned to marry and live together on the Avery family lot in Manitowoc Country, Wisconsin.

However, just two years after Avery was cleared of a rape he spent 18 years in jail for, he found himself at the centre of another investigation.

At the time, Avery was in the process of suing his local police department for $36 million.

The show argues Avery was framed by the local department and evidence planted on his property, including Avery’s own blood.

Avery recently filed a motion to dismiss his conviction based on that theory, and on the theory his jury was coerced into delivering a guilty verdict.

Passionate viewers of the show have called for Avery’s release, with one petition racking up over 400,000 signatures – enough to warrant an official response from the White House.

Watch the teaser video below:

Steven Avery’s ex-fiancée says “he is not innocent,” calls him a monster #MakingAMurdererhttps://t.co/ngEQIGFKKFhttps://t.co/y3NyjgKRYw

— CNN (@CNN) January 13, 2016