Exclusive: Mum cleared of murdering children defends Australia's worst female serial killer

A mother cleared of murdering her four children has defended Australia’s worst female serial killer Kathleen Folbigg, who is currently serving a 30-year jail sentence.

Carol Matthey was accused of killing her four children, Jacob, seven months, Chloe, nine weeks, Joshua, three months, and Shania, three and a half years old, between 1998 and 2003.

The highly-publicised murder trial ended suddenly when the judge threw out the medical evidence against her – which relied on ‘Cot Death Theory’, an academic report made famous by British Professor Roy Meadow.

The theory claimed that one cot death is a tragedy, two is suspicious, and three is murder; the same model used to convict and jail Kathleen Folbigg in 2003.

A landmark inquiry reviewing Folbigg’s conviction begins tomorrow, focusing on medical evidence – specifically the occurrence of the deaths of three or more children due to natural causes.

The inquiry speared Matthey to break her silence and tell her tragic story for the first time in an exclusive 60 Minutes interview.

She told reporter Tara Brown she hopes that by speaking out, Australia will accept her inconceivable truth: the deaths of four babies from the same family could be a medical mystery and not a sinister series of murders.

“[I’m] someone dealing with an unimaginable amount of grief,” she told Brown.

“I’d do anything to have all my babies back.”

Between 1998 and 2003, four of Matthey’s children died in her care.

In 1998, her son Jacob passed away aged seven months. Two years later, Chloe died at nine weeks.

Forensic pathologists said both children suffered from SIDs.

In a devastating blow, three-month-old Joshua died less than two years later from a suspected blood infection.

“I can’t remember exactly what I was thinking but I think the main thing was, it can’t be happening again,” Matthey told reporter Tara Brown.

But when Matthey’s daughter Shania died – aged three and a half and considered too old for SIDs – police and medical experts became suspicious.

Matthey was accused of murdering her four children and became reviled as the ‘kiddie killer’ in her community. In the court of public opinion, she was guilty.

“It hurt a lot, which made me not want to go out and I just sheltered myself from everyone and stayed at home,” she said.

Matthey denied four times over to reporter Brown of ever harming or killing her children.

“I don’t know why anyone would want to murder their children, especially four.”

The Victorian Supreme Court never convicted Matthey of murder, stating the medical evidence didn’t prove foul play.

Matthey walked free. But just a few years earlier, Folbigg was charged and then convicted of the same crimes.

Calab, Patrick, Sarah and Laura all died in Folbigg’s care between 1989 and 1998.

At the time of Folbigg’s trial there had been at least eight other cases around the world where three or more children from the same family died from natural causes.

But in a pre-trial hearing for Folbigg, experts cited Meadows’ ‘Cot Death Theory’ – and said that the chance of four unexplained infant deaths from natural causes was “one in a trillion.”

In 2003, she was charged and convicted of three counts of murder and one count of manslaughter. Folbigg has always maintained her innocence.

Social Justice lawyer Michael Nott believes Folbigg should never have been charged, and claims there was no sufficient medical evidence to convict Folbigg.

“Kathleen should never have been charged and brought to trial originally. It’s a gross injustice that needs to be rectified,” he told 60 Minutes.

Matthey hopes that by sharing her story for the first time, she will change not only Folbigg’s conviction in court, but also in public opinion.

“As we learned with my case the medical experts can get it wrong and do get it wrong,” she said.

“She could very well be innocent.”

If the inquiry goes her way, Folbigg may have a re-trial, with the potential to result in her convictions being overturned.

To watch ‘Inconceivable’ in full and for more from 60 Minutes, visit the official website

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