The lawyers from the documentary Making a Murderer say they are excited about new forensic DNA testing methods that could finally prove Steven Avery was framed.

Since the 10-hour series aired last year, the two middle-aged lawyers from Wisconsin have become unlikely cult figures.

Dean Strang and Jerry Buting have been compared to Atticus Finch, and have been the subject of T-shirts, tweets and even a blog dedicated to their fashion sense.

They have parlayed their notoriety into an Australia-wide tour, speaking about the Avery case and its broader implications.

Loading

The lawyers told Lateline they are "excited" about new scientific testing methods that might be able to radiocarbon date blood found at the scene of the crime.

"Probably over 100 scientists all over the world between the two of us contacted us [after the documentary] and said hey, you know there's new tests you can do," Mr Buting said.

Since the show aired, Avery has retained a new lawyer, Kathleen Zellner, who specialises in wrongful convictions.

In August she filed a motion at the Manitowoc Circuit Court demanding scientific testing that did not exist at the time the case was tried be conducted.

"We actually were contacted before she was retained," Mr Buting said.

"Some of it was just, oh our ability to detect EDTA, chemical tests have been refined, but some of the more interesting ones were these scientists with things like radiocarbon dating and DNA ageing, it's called, where you can actually look at somebody's sample of blood maybe a month or a year ago and distinguish it from their blood right now."

Mr Strang hopes the DNA ageing method will prove Avery is innocent.

"If it turns out that the blood in the Toyota is older than the car itself — is 10 years older than the time at which it's found and five years older than the ca — then that's also good at getting us to the truth," he said.

"And it also will mean not only a new trial I think for Steven Avery, but the likelihood that he walks free, because his blood from the mid-90s, if it's in that car, then Steven Avery was telling the truth when he said it was planted."

Brendan Dassey is pictured in this undated booking photo. ( Reuters: Manitowoc County )

'I've always believed that he's innocent'

It was 11 years ago that 25-year-old Teresa Halbach went missing in Manitowoc County on an early evening on Halloween.

The Avery junk yard where Teresa Halbach's vehicle was discovered. ( Imdb: Netflix )

The young photographer was last seen with Steven Avery when she went to his home to take pictures of a car he had for sale.

When Ms Halbach's charred remains were found on Avery's property, he and his nephew Brendan Dassey were arrested and charged with her murder.

Avery had only just been released from prison two years earlier after spending 18 years behind bars for a violent rape it was later proved he did not commit.

Both Avery and his nephew were found guilty of Ms Halbach's murder, but Mr Buting said he never thought the state's case added up.

"I've always believed that he's innocent for a lot of reasons," he said.

"They never had a motive for him to do this, he was about to come into $400,000 tax free cheque from the state that very week that she disappeared, that's over and above the $36 million lawsuit he had that was also succeeding."

In August this year, the worldwide spotlight on the case helped overturn Brendan Dassey's conviction, and he is now set to be released from prison.

'100,000 amateur sleuths'

Mr Buting and Mr Strang said successful true crime documentaries such as Making a Murderer, the Jinx and the podcast Serial could change the way high-profile cases are investigated.

"In these particular cases the fact that a documentary covered them and they're so widely disseminated may actually help them down the road on appeal," Mr Buting said.

"It may still help Steven Avery because people come forward with factual information or scientific information that can be used now that probably wouldn't have if (it weren't for) the documentary."

Mr Strang said while lawyers would not turn to documentaries as a defence strategy, it may open the door for citizen investigators.

The Netflix series has a cult following and spawned countless citizen investigators.



"Some of these recent entrants to the true crime genre, like Making a Murderer, suggest a future in which in fact either prosecution or defence might be crowdsourced," he said.

"That we might turn to 100,000 amateur sleuths with evidence and wait and see what people find, what people notice, what connections people make.

"There's no reason that that sort of crowdsourcing, if you'll accept that term, would be limited to the defence side in criminal cases or would be limited to criminal cases at all."



But Mr Buting is quick to point out that the Making a Murder documentary had the benefit of examining a case after it had been before a court.



"It's different when it's after the conviction because then police reports, the kind of inside detail information that's now uploaded and available for people to look at in the Steven Avery and Brendan Dassy case, before the trial is done you're not allowed to do that," he said.

"I mean there are limits. You can't just, as a defence or prosecutor, just upload these police records for anybody to look at."