It was James Spyridon Vlassakis’s testimony that helped convict Snowtown murderers John Bunting and Robert Wagner.

The youngest of the four perpetrators involved in South Australia’s “bodies-in-the-barrels murders”, Vlassakis was the key prosecution witness.

Bunting and Wagner were convicted of 11 and 10 murders respectively and are in prison for the rest of their lives with no prospect of parole.

Vlassakis also helped put Snowtown accomplice Mark Ray Haydon away for 25 years. The 65-year-old’s sentence ended last week.

Mark Ray Haydon, Robert Joe Wagner and John Justin Bunting were jailed for their involvement in the Snowtown murders.(Supplied: Tim Ide)

Vlassakis, who was 19 when he committed the crimes, was found guilty of being involved in four of the murders and received a life sentence.

Because he had assisted authorities, Vlassakis was given a non-parole term of 26 years and his image remains suppressed to this day.

His role and involvement were given prominence in the Snowtown murders movie — a story told from his perspective.

Now at 44, Vlassakis will be eligible to apply for parole in May next year.

A key person he will need to persuade is the chair of the South Australian Parole Board, Frances Nelson KC.

“We review his case annually, any prisoner with a life sentence has to have their case reviewed annually,” Ms Nelson told ABC Stateline.

“And that’s helpful if they apply for parole because you’ve monitored them throughout many years.”

But Ms Nelson would not be drawn on Vlassakis’s parole prospects.

“I’m not prepared to discuss that because, to begin with, he hasn’t applied for parole,” Ms Nelson said.

“I assume he will and we’ll then judge his case on its merits, but I wouldn’t want to pre-empt a decision by the board.”

Vlassakis was pulled into the serial killings by his stepfather Bunting, who he lived with along with his mother in Adelaide’s northern suburbs.

Bunting, Wagner show no contrition

The files of Bunting, along with other main offender Wagner, are also reviewed annually by the parole board.

Wagner has tried, and failed, to have a parole date set so he can have the prospect of release

Bunting has not made any application but has appeared before the parole board.

Eight bodies were found in acid-filled barrels in a disused bank at Snowtown.(ABC News: Che Chorley)

Ms Nelson said they have both shown no contrition for their crimes.

“They’re obviously very unpleasant people,” Ms Nelson said.

“I don’t get the impression that either of them is particularly remorseful for what they did.”

When asked if Bunting remains proud of what he had done, Ms Nelson said: “he certainly can give that impression”.

Media scrutiny ‘inhibited’ Haydon’s resocialisation

Ms Nelson said the parole board continues to have a role in monitoring Haydon, who was released last week to live in the community with strict supervision after spending 25 years in jail.

In 2006, Haydon was convicted of seven counts of assisting an offender, for storing the bodies-in-the-barrels at his Smithfield Plains home in Adelaide’s north and for helping to move them when police became suspicious.

The parole board chair said she considered Haydon a low-risk offender and a different man from the one who was first taken into custody in May 1999.

While on parole at the Adelaide Pre-release Centre, Mark Haydon ventured out on supervised day release.(ABC News: Che Chorley)

“We wouldn’t be releasing him if we didn’t have that level of confidence,” Ms Nelson said.

“We do undertake a very careful risk assessment and in his case, it took longer because of the association with Bunting and Wagner.

“You can never predict with complete accuracy, what’s going to happen in anyone’s future but I think with him, he’s likely to be fairly reclusive.”

Ms Nelson said while on parole Haydon had, at one stage, refused to leave the Adelaide Pre-release Centre at Northfield where he was living.

“The media scrutiny inhibited his resocialisation because he was anxious enough, being released into the community [with] the ordinary daily challenges that he would face,” Ms Nelson said.

“Because of the intensive media scrutiny, in the end, he refused to go out.

“So that, to some extent, it setback his resocialisation.”

Ms Nelson said the 65-year-old “got over it” but it took a few days.

“He’s a bit of a loner and passive sort of individual, which I suppose is why he was under the thrall of Bunting in the first place,” she said.

“I don’t think he’ll go out looking for trouble…I think he just wants to lead a quiet life.”

Frances Nelson says prisoners with life sentences have their case reviewed by the parole board annually.(ABC News: Lincoln Rothall)

Haydon has been placed under an interim supervision order, similar to his parole conditions.

He has a curfew, can’t go to licenced premises, contact victims and their families or contact his fellow offenders.

Haydon also has to wear an electronic monitoring bracelet and report regularly to corrections officers and follow their directions.

“We have charge of supervising him and ensuring he complies with the conditions,” Ms Nelson said.

“They’re fairly similar to the parole conditions, except they don’t have exclusion zones, which we were looking at.

“Because the victims don’t want him going in certain areas, but the court hasn’t imposed those conditions as far I can tell.”

SA Attorney-General Kyam Maher maintains there are exclusion zones that corrections oversee.

“Community corrections manage that, my understanding is it’s often specific areas of the city or suburbs that people are excluded from,” Mr Maher said.