The sons of murder victim Maria James have moved one step closer to having her 37-year-old cold case reopened by the coroner.

The single mother was stabbed to death in the back of her Thornbury bookshop in June 1980.

The Victorian state coroner, Sara Hinchey, has written to the James brothers advising that she is considering their application to hold a new inquest.

But there's a small stumbling block.

The coroner is unsure whether she has the jurisdiction to hear the matter, given the 1982 inquest finding falls under an old act of the Victorian Coroners Court.

She now inviting submissions as to whether she or the Supreme Court should hear the case.

Mark James said it's not the answer he was hoping for after waiting six months, but it at least represents some progress.

Mark James has been seeking answers over his mother's death his whole life. ( ABC RN: Jeremy Story Carter )

"It was a bit disappointing that it took so long, but I understand it is a complex legal issue for the coroner, and I have every faith in the justice system," Mr James said.

The James brothers applied for a new inquest after evidence was uncovered last year by the ABC's Trace podcast.

Father Anthony Bongiorno abused Adam James. ( ABC )

The investigation revealed a priest, Father Anthony Bongiorno, who was discovered to have been molesting Maria's son Adam, was seen by an electrician near the crime scene covered in blood on the day of the murder.

Victoria Police has since admitted it was wrong to rule the priest out as a suspect on the basis of DNA, because a bloodied pillow thought to have yielded the killer's DNA was actually from a completely different crime scene.

Mark James wants the coroner to look into the DNA bungle, and the potential murder motive that has come to light.

"Two priests had been sexually assaulting my brother just prior to the murder, and mum found that out just prior to the murder and had confronted them," he said.

"Back then that kind of thing wasn't on anybody's mind, civilians or even the police."

Former top-cop wants coroner to reopen case

The Victorian Coroner's Court Act of 2008 states that the coroner can make an order to re-open a case if "there are new facts and circumstances."

Retired detective, Ron Iddles, whose first homicide investigation was the Maria James murder, believes the coroner has the power to re-open the case.

"I think the coroner does have the authority because Section 77 (of the Coroner's Court Act) is pretty clear — if you want to re-open a previous inquest, you've just got to have good information to do it," he said.

"That section in itself gives the coroner the power to do it."

A decorated former senior-sergeant considered among Australia's finest ever detectives, Mr Iddles said there was compelling new information to warrant a fresh inquest.

"The new material that should be put before the coroner to make an assessment is the evidence of Adam James, where he says he was sexually assaulted by Father Bongiorno, and the evidence of the electrician," he said.

The murder of Maria James was Ron Iddles' first case as detective. ( ABC RN: Jeremy Story Carter )

"You have Adam saying, 'two days previously, I was assaulted by Father Bongiorno [and] my mum was going to confront him.'

"The electrician came forward, [saying] that he was present at the [nearby St Mary's] presbytery on the day of the murder and he saw Father Bongiorno covered in blood."

Mr Iddles said there is precedent for the coroner to rule on this case. In 2011, coroner Jennifer Coate was asked to set aside the 1998 finding that former police officer Denis Tanner shot dead his sister-in-law Jennifer Tanner.

The coroner will hear submissions on whether the decision to reopen this case should fall to her, on January 30.

Following discovery of the DNA bungle, revealed by the Trace podcast, Victoria Police committed to retesting exhibits from the Maria James crime scene in the hope of securing a DNA profile of her killer.

Investigators would not comment on any potential developments, as the matter is ongoing.

Mr Iddles is still hopeful some form of justice can be achieved for the James brothers.

"It will never bring Maria James back for the family, but what it will do, once and for all, is give them some answers about what might have happened," he said.