Kathleen Folbigg: expertise on trial over notorious child deaths

Case of Australia’s ‘most hated woman’ highlights tensions between justice, science and courts’ need to distinguish between world experts and ‘proven performers’

July 10, 2022
Kathleen Folbigg appears via video link during a convictions inquiry at the NSW Coroners Court, Sydney, New South Wales, Australia, 30 April 2019.
Source: Shutterstock

When 75 eminent Australian scientists and doctors went in to bat for the country’s “most hated woman”, they raised new questions about the sometimes fraught relationship between justice and science.

Kathleen Folbigg was jailed for decades in 2003 for smothering her four infant children over the space of nine years. The horror of the crimes and Folbigg’s stoic demeanour engendered little sympathy for the woman dubbed “Australia’s worst female serial killer”.

However, forensic experts harboured doubts about Folbigg’s conviction, which was based on circumstantial evidence – the supposedly minuscule probability of four children from one family dying from unidentified natural causes – along with incriminating entries in her diaries.

Folbigg exhausted all avenues of appeal. But in 2018, the New South Wales (NSW) governor ordered a fresh inquiry into her conviction, several years after a petition had offered new evidence in her defence.

Its authors claimed that forensic pathology discussions at her trial had been “misconceived” and that there was no medical basis for concluding that she had killed her children. A psychological report also challenged suggestions that her diaries included admissions of guilt.

The claims were dismissed in the judicial inquiry’s 500-page report. “Her own explanations and behaviour in respect of her diaries makes her guilt of these offences even more certain,” concluded former NSW District Court chief judge Reginald Blanch.

In early 2021, sceptics doubled down in a new 14-page petition seeking not merely an inquiry but a pardon, saying the justice system had wrongfully incarcerated a woman who had already endured the loss of four children.

The petition explained that sequencing of the Folbigg children’s genomes during the earlier inquiry had revealed that the two girls, Sarah and Laura, carried previously unknown mutations in a gene known as calmodulin 2, which had long been associated with sudden infant death.

The month after the inquiry’s hearings in April 2019, it was reported that a similar mutation had caused the deaths of two US siblings. This had been made known to the judge before he issued his findings, in statements unsuccessfully seeking the inquiry’s extension.

The second petition, which was signed by 16 foreign luminaries as well as 75 Australians, also offered expert medical explanations for the deaths of the two Folbigg boys, Caleb and Patrick – breathing difficulties in one case, and epilepsy in the other – suggesting that any “reasonable person” would doubt Folbigg’s culpability.

Its signatories included a who’s who of Australia’s scientific elite, including Nobel laureates Elizabeth Blackburn and Peter Doherty, cervical cancer vaccine developer Ian Fraser and former chief scientist and Australian National University (ANU) vice-chancellor Ian Chubb.

“I signed it because I read the papers,” said Professor Chubb. “The evidence was, in my view, strong enough to…warrant further investigation. I thought that I had an obligation to put my name to the petition, and I would do it again.”

Professor Chubb said the genomic sequencing capabilities that produced the new evidence had not existed at the time of Folbigg’s conviction. “Some of the technologies now at our disposal are orders of magnitude more sensitive than the ones that were around 20 years ago. Science can get ahead of the law.”

In May this year, NSW attorney general Mark Speakman recommended a fresh inquiry instead of a pardon, citing the need for transparency. “If people are to be confident in our justice system, they have to see it in action,” he said.

Mr Speakman said evidence raised during and after the earlier inquiry – particularly research published in 2020 by the European Society of Cardiology, showing that both Folbigg and her two daughters had carried the previously unknown genetic variant – had reached “the necessary threshold for some kind of intervention”. But the significance of the mutation had been a source of “disagreement” between two groups of experts during the earlier inquiry.

The 2020 paper was authored by 27 researchers from 16 institutions in six countries. They included two scientists who had urged the previous inquiry’s extension: Milan-based cardiologist Peter Schwartz, a globally recognised expert in inherited arrhythmias who had established an international registry of calmodulin mutations, and Danish protein chemist Michael Toft Overgaard, who had analysed many calmodulin mutations in his laboratory.

Fellow author Carola Vinuesa, who had first identified the new variant after sequencing Folbigg’s genome before the earlier inquiry, said she had turned to the pair as the world’s foremost experts in the field. “There was a point in the court where there were two groups of experts saying different things,” said Professor Vinuesa, who headed the ANU’s Centre for Personalised Immunology at the time.

“You had a group of clinicians saying that calmodulin mutations do not cause death in children who are very young or asleep. I’m not a cardiologist, and I’m not sure that any of the so-called experts in the room had ever diagnosed a child with a calmodulin mutation. But Professor Schwartz, who knew in depth the types of death caused by calmodulin mutations, wrote to the judge explaining that these mutations did indeed cause deaths in young children during periods of sleep. Sadly and incomprehensibly, his expert report was ignored.”

Having been persuaded to look into the case by a lawyer and former student, Professor Vinuesa had begun with a “very open mind” but had become steadily more convinced that the deaths had compelling genetic explanations. She said the legal system needed better tools to evaluate scientific evidence. This included advice for judges on “who are the experts in the field”.

Ian Connellan, editor-in-chief of the Royal Institution of Australia, said such tools existed elsewhere. The US Federal Rules of Evidence, for instance, allow only expert testimony that is “based on sufficient facts or data” produced using “reliable principles and methods”.

“In some jurisdictions, there are now expert committees that review scientific evidence and report [its validity] to the court,” said Mr Connellan, whose magazine Cosmos has reported extensively on the Folbigg case. “In Australia, there are no special requirements. Scientists like Carola do careful work, make discoveries [and] get these discoveries peer-reviewed. But [people would] rather rely on some lines written in a diary by a clearly extremely emotionally distressed young woman some years ago, against properly validated and proven scientific evidence.”

Mr Connellan said he suspected that judges and juries struggled to identify “genuine” world experts. “A jury could be listening to an acknowledged international expert…or a general medical practitioner who has proven over time to be a very capable court performer. If you know a forensic scientist who is a proven performer in the high-octane atmosphere of an adversarial court, that’s who you’re going to get – even if he or she’s not an expert in this area.”

University of Sydney law lecturer Jason Chin said courts were not immune to the types of poor practice that plagued research, such as scientists overstating the robustness of their findings and resisting corrections to their work when flaws were found.

Dr Chin said the types of safeguards employed against dodgy science, such as the use of randomised controlled trials, should apply when academics appeared as court witnesses. “If they’re being paid, they shouldn’t be told who they’re being paid by. Ideally, they should be paid…by both parties or the court or some sort of public fund, because there are all kinds of unconscious ways that you can bias the results,” he said.

The ethos underpinning criminal justice proceedings – advocating a predetermined position about someone’s guilt or innocence – seems anathema to the academic ideal of following the evidence and not prejudging anything. Dr Chin said this was just one of many tensions between academic research, which often moved quite fast and aspired for precision, and the justice system’s generally slow pace and its tendency to resist defining fundamental concepts such as “beyond reasonable doubt”.

He said the legal world’s “principle of finality” was evident in things such as limits on the number of appeals. “You want there to be a final decision at some point so people can move on with their lives. People generally like certainty, yet…science strives to embrace uncertainty.”

NSW attorney general Mr Speakman was almost apologetic when he announced the latest inquiry: “I can well understand why members of the public may shake their heads and roll their eyes in disbelief about the number of chances that Folbigg has had to clear her name.” While the “nature of the scientific evidence” had left him with little option about pursuing a further review, he said the decision would “weigh on all our shoulders”.

Folbigg’s former husband Craig, who had endured the loss of four children and the conviction of his wife, had been forced to “relive it all again through a public inquiry in 2018 and 2019 and will have to go through it yet again in 2022”.

The episode has also weighed on the academics whose research convinced them that Folbigg had suffered a shocking injustice. “It has taken a bit of a toll,” said Professor Vinuesa, who recounted the ordeal in The Conversation. “Psychologically, I found the whole process very distressing and stressful.” Bringing experts together, writing “endless” reports for the first inquiry and then publishing the group’s scientific experiments had also proven extremely time-consuming.

She, too, faces reliving the experience. The counsel assisting the latest inquiry, which began in Sydney in late June, reportedly recommended that Professor Vinuesa – now a principal group leader at London’s Crick Institute – be called to give evidence, along with Professor Schwartz.

But as a person, an academic and a medical doctor by training, she felt obliged to get involved. “We swear the Hippocratic oath, when we become doctors, essentially that we are going to try and do the best and most ethical thing for our patients. The truth is important. It’s something that I also see as part of my work as an academic. You work hard on the things that you believe in.”

But Dr Chin said most academics who intervened in court battles faced a steep learning curve. “When you take a job at a university, no one tells you how to do this kind of thing. It’s completely left up to you about how you engage with the media, legal issues, court battles, policymakers.

“We’re told that they want us to engage. They want us to have an impact; to inform how laws and court decisions develop. But in the end, there’s no guidance on the responsible way to do that.”



Print headline: Notorious child deaths case puts expertise on trial

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Reader's comments (2)

My favourite example - most people fail this one - ask "There is a disease X that only 1% of the population has. We have a test for X that is 98% accurate. Forensics tell us the perpetrator had X. The suspect has just tested +ve for X. How likely is he to have the disease"................... Your answer, as a member of the Jury?.......... OK, of every 10,000 people, 100 will have X and 9,900 won't. Of those groups, 98 of the 100 will test +ve, AS WILL 198 of the 9,900 (test is 98% accurate). So we get a total of 297 +ve tests results, of who just ONE THIRD have X. But what did you the jury say?
Case like these are relatively common, such as the tragic case of solicitor Sally Clark in the UK, https://en.wikipedia.org/wiki/Sally_Clark who was found guilty on the basis of flawed statistics presented by the expert witness. Could there have been other factors? For example, standard advice to sleep babies on their front, promoted by the best selling "Baby and Child Care" by Dr Benjamin Spock since the 1940s, was been credited with causing over 60,000 infant deaths worldwide up until 2005. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222341/ It is worth reflecting on the persistence of both the 50 Million physical copies, and the advice they contained, especially when the book, translated into 42 languages, was considered the "bible for both professionals and parents". "Back to sleep" campaigns in the UK (1991) and US (~1994) reduced SIDs by around 75%, but did similar campaigns take place elsewhere?