Folbigg was convicted in 2003 for the murder of three children, and the manslaughter of a fourth, although there was ‘‘no forensic pathology support for the contention that any or all of these children have been killed,’’ internationally respected Monash University Professor of Forensic Pathology Stephen Cordner said as part of the petition.

‘‘If the convictions in this case are to stand, I want to clearly state there is no pathological or medical basis for concluding homicide.’’

Newcastle barristers Robert Cavanagh, Nicolas Moir and Isabel Reed, and University of Newcastle Legal Centre director Shaun McCarthy, sent the petition to NSW Governor David Hurley on June 11, seeking a judicial review, after serious concerns about the convictions were first raised by legal academic Dr Emma Cunliffe in her 2011 book, ‘‘Murder, Medicine and Motherhood’’.

The petition has argued the Folbigg convictions were unreasonable in light of more recent knowledge about children’s sudden deaths, particularly relating to cardiac conditions, and the trial’s acceptance of a default diagnosis of murder after incorrect evidence about the incidence of four children’s deaths in one family.

The weight of new evidence was significant, the petition argued, and greater than the ‘‘unease and disquiet’’ standard required to justify a judicial review of the case.

A case that included incorrect medical evidence, incorrect evidence about the incidence of four children’s deaths in one family, a default diagnosis of murder when there was no medical evidence to say they had been killed, made the convictions unreasonable, the petition said.

In a 120-page report Professor Cordner, who is also head of international programs at the Victorian Institute of Forensic Medicine, found much of the forensic pathology discussed at the trial was ‘‘misconceived’’.

He found the default diagnosis of murder was ‘‘wrong’’ and there was no forensic pathology support for the Crown case that Kathleen Folbigg smothered her four children between 1989 and 1998.

‘‘It seems not to have been explicitly stated in the trial, but there is no forensic pathology evidence, no signs in or on the bodies, to positively suggest that the Folbigg children were smothered, or killed by any means,’’ Professor Cordner said in his report.

The petition challenges evidence at the trial that three or more unexpected deaths from natural causes in a family had never occurred before.

It includes a report by leading United Kingdom statistician and professor of mathematics Ray Hill, who said the jury was ‘‘almost certainly misled’’ about the rarity of multiple sudden infant death syndrome cases in families.

Evidence that there were no known cases of three or more SIDS deaths in a family was not only wrong, but would have left the jury in 2003 discounting SIDS, and ‘‘leaving multiple homicides as the only explanation’’, Professor Hill said.

A large American study in 1987 included two families where four babies had died of SIDS and related conditions, and later United Kingdom and Norwegian studies of SIDS included a number of families where three babies had died.

The studies concluded that babies born in families where one child had already died of SIDS were up to 10 times more likely to become SIDS victims.

The ‘‘risk of adverse outcomes [was] significantly greater’’ for babies where two or more previous siblings had died of SIDS, they found.

The petition will also include a psychological report challenging the suggestion Mrs Folbigg’s personal diaries included admissions of guilt about killing her children.

A clinical psychologist found Mrs Folbigg’s diary entries were consistent with psychological literature of the thoughts and feelings of mothers whose children had died, and maternal grief reactions.

There was no attempt by Mrs Folbigg to conceal her private writings, the petition said.

Mr Cavanagh said Professor Cordner’s report alone raised significant doubt about the Folbigg convictions.

‘‘What we’re simply saying is that there may be a miscarriage of justice here, and this real possibility needs to be considered by a judicial review.’’

The petition was expected to be forwarded from NSW Governor David Hurley to NSW Attorney-General Gabrielle Upton, and from there to the NSW Crown Solicitor’s office for consideration of a judicial review of the case.