For Ms Folbigg’s loved ones and supporters, the last 24 years have been an emotional and considerable fight to prove she is not guilty of murdering her four infant children: 19-days-old Caleb, eight-month-old Patrick, 10-month-old Sarah and one-year-old Laura.

Over a fortnight in April this year, world-leading experts gave evidence at an inquiry before NSW’s former Chief Justice Tom Bathurst about a genetic variant that was found in Ms Folbigg and could be the cause of the deaths of her daughters Sarah and Laura.

The inquiry also heard evidence about the deaths of her sons and the contemporaneous diary notes that the original prosecution team from the 2003 hearing relied on to suggest her guilt.

At the end of the explosive inquiry evidence, the inquiry’s own counsel assisting submitted it is open for Mr Bathurst to “conclude there is reasonable doubt as to Ms Folbigg’s guilt”.“The bare fact of the coincidence of four unexplained infant or young child deaths alone cannot prove guilt beyond reasonable doubt,” lawyers Sophie Callan SC, Julia Roy and Naomi Wootton found.

In another “huge moment” for Ms Folbigg, the NSW Director of Public Prosecutions, Sally Dowling SC, agreed with counsel assisting.

With all this evidence stacking up, Ms Folbigg’s legal team have questioned why the NSW government, and particularly Attorney-General Michael Daley, has not yet released her — either on a pardon or on parole to await Mr Bathurst’s findings.

“Hearing all the compelling evidence, hearing submissions by the counsel assisting the inquirer that there is reasonable doubt, hearing that the director of public prosecutions has said it is open to Mr Bathurst to find reasonable doubt all points to an innocent woman languishing in prison," Ms Rego said.

VIEW ALL

"The scientific evidence and evidence relating to the diaries in particular is incredibly powerful. The submissions by counsel assisting the inquirer and the director of public prosecutions are a testament to the strength of the evidence.

"It's clear there is an innocent woman in gaol and the Attorney General is the only person who has the ability to let Ms Folbigg out now. That's what we're asking him to do. We have been asking and asking but our requests have been met with silence."

Not only did the inquiry conclude with counsel assisting submitting it is open to find reasonable doubt, but Ms Rego added the lawyers said it was open to finding Ms Folbigg “was not angry or frustrated towards her children on a consistent basis”.

“Counsel assisting submitted that the weight of the evidence tends to suggest that Kathleen was a loving and caring mother towards her children. Kathleen has been waiting for acknowledgment of this truth for 24 years,” Ms Rego said.

What the inquiry was told about Ms Folbigg’s innocence

Much of the inquiry focused on the genetic mutation CALM2 G114R, which was recently added to the list of mutations on ClinVar — the worldwide authoritative database used by clinicians and geneticists.

This variant mutation was discovered in Ms Folbigg and in both her daughters, which suggests the girls died from the legal mutation rather than the crimes their mother was convicted for.

World-leading experts were invited to the inquiry to discuss the variant, and all but one said it was a reasonable possibility of death.

“Despite some minor disagreement between genetic and cardiology experts, none of them could rule out the cardiac variant CALM2 G114R as a possibility for the deaths of Sarah and Laura,” Ms Rego explained of the evidence.

The inquiry also touched on an event in October 1990 in which Patrick had a “failed smothering event”. Ms Folbigg was charged with causing grievous bodily harm as a result.

Ms Rego said the prosecution at the 2003 trial had no evidence in respect of Patrick except for a death certificate citing epilepsy and this one event prior to his death. An expert suggested during the inquiry that this event could be linked to a neuro-genetic condition.

Dr Monique Ryan, an MP with extensive experience in paediatric neurology, concluded Patrick’s epilepsy may have started on the day of this event, and she is “in favour of a natural cause of death”.

Her evidence was supported by Professor Peter Fleming, a world-leading expert on sudden deaths, who gave some evidence about the October 1990 alleged “failed smothering event”.

“In relation to Patrick, Professor Monique Ryan and world leading experts in sudden death, Professor Peter Fleming, agreed that his death was not a result of a failed smothering event four months earlier,” Ms Rego said.

"According to them, the medical documentation recorded at the time points away from this proposition. There was agreement that his death was from epilepsy."

As for Caleb, while there is no new evidence, counsel assisting acknowledged that with the strong evidence for Sarah, Laura and now Patrick, “there is a lot of doubt around Caleb too”.

“The five convictions rested on coincidence and tendency evidence. It's like a domino train. If one of the convictions fail, the rest of them falls,” she said.

Caleb was a sick child in the 19 days of his life. He had respiratory distress syndrome and laryngomalacia in which he could not breathe and swallow simultaneously. It is not surprising he died, Ms Rego added.

"There are also some suspicious genetic variants discovered in Caleb, but his father refusing to give his DNA for the purpose of genetic investigation hampered our efforts to discern which of those variants might have caused his death."

The inquiry also focused on the diaries, which the original prosecutors alleged contained confessions of guilt.

This has been heavily debated by Ms Folbigg’s legal team and her closest loved ones, who have insisted for many years that the diaries were “cherry-picked” for certain phrases and there was never anything in them to suggest premeditated murder or harboured rage.

Many experts briefed by the prosecution at the inquiry all agreed that the diaries were not confessions of murder.

“It was a huge moment,” Ms Rego said.

What happens now?

Ms Folbigg’s legal team and her loved ones said they are essentially in limbo while they wait for Mr Bathurst to make his findings — but that does not mean they want him to rush.

“Mr Bathurst has an enormous task in preparing the final report. If he finds reasonable doubt, and he refers the matter to the Court of Criminal Appeal, his report will be instrumental in the quashing of Ms Folbigg's convictions. It's in everyone's interests that it is detailed and comprehensive,” Ms Rego said.

Ms Rego said Mr Bathurst has the power to refer the case to the Court of Appeal. Ms Folbigg’s legal team has also asked him to report to the governor that there is a proper basis for a pardon.

For now, though, they have focused their attention on Mr Daley.

“Mr Bathurst's job is to decide if there is a reasonable doubt on the evidence. Attorney General Michael Daley's job is to recommend to the Governor that she can pardon Kathleen Folbigg or give her early parole. That is his job and he should do it now,” Ms Rego said.

In a letter addressed to Mr Daley, 14 academics in law and legal fields have made a similar request to release Ms Folbigg on an “interim basis immediately” pending the next steps.

They write that there is an Australian precedent for “releasing an exonerated prisoner pending the completion of legal processes associated with their guilt” following Lindy Chamberlain’s matter.

Ms Chamberlain was incarcerated for the death of her child Azaria but insisted a dingo was the real reason. When Azaria’s jacket was found at Uluru, Ms Chamberlain was released in February 1986 while an inquiry into her conviction took place.

This inquiry cleared Ms Chamberlain of all responsibility.

Signatory Associate Professor Mehera San Roque, from the University of NSW’s faculty of law and justice, told Lawyers Weekly that the academics have had a “longstanding interest and longstanding concerns” about Ms Folbigg’s matter.

“We felt it was important to signal that in light of the (inquiry) submissions, it would be important and appropriate for Ms Folbigg to be released immediately pending final resolution rather than her remaining incarcerated,” Associate Professor San Roque said.

Where is the Attorney-General in all of this?

A loved one of Ms Folbigg told Lawyers Weekly it has been frustrating that the government has continued to keep Ms Folbigg behind bars despite the mountain of evidence.

“It’s very frustrating because right now, we’re in a territory where we shouldn’t be, and I’m losing my patience. It’s not right, it’s not humane, and it’s unacceptable. I don’t get why people have the power to keep digging their heels in when they’re wrong,” she said.

Ms Rego said that, leaving aside the empathy the government should be feeling for Ms Folbigg, “this is a factual matter”.

“The other thing that is striking to me is he could at least say that in the event that Mr Bathurst finds reasonable doubt, then he will recommend immediately a pardon. It is simply cruel, objectively cruel to Kathleen not to do that,” Ms Rego said.

A spokesperson for Mr Daley said they were unable to make a determination in advance of receiving advice from the inquiry "given the extensive judicial consideration, and the breadth of technical scientific and legal evidence being considered".

"This government was elected with a mandate to act on expert advice when it comes to decisions across government.

"The Attorney General will work to expedite any recommendations regarding Ms Folbigg which may result from the inquiry," the spokesperson said.