An Australian woman has been jailed for life, with no chance of release for at least 33 years, for murdering three relatives and trying to kill another with a toxic mushroom meal.

The jail term, one of the longest ever handed to a female offender in Australia, means Erin Patterson, 50, will be in her 80s before she can apply for parole.

A Supreme Court judge said Patterson’s crimes were the “worst category” for offending and involved an “elaborate cover-up”.

Patterson killed her in-laws Don and Gail Patterson, both 70, and Gail’s sister Heather Wilkinson, 66, after serving them a toxic beef Wellington at her home in Victoria in 2023.

Heather’s husband Ian Wilkinson, a local pastor, survived the lunch after recovering from a coma and has ongoing health issues related to the poisoning.

Patterson’s estranged husband Simon Patterson was meant to attend the lunch too but cancelled at the last minute, in part due to his belief that his wife had been trying to poison him for years.

Patterson has long maintained her innocence, saying the toxic death cap mushrooms in the dish she prepared were accidentally added and that she never intended to harm her relatives.

She will serve three consecutive life sentences for the three murders and 25 years for the attempted murder of Mr Wilkinson.

During his sentencing remarks, Justice Christopher Beale said the gravity of Patterson’s crimes meant he must impose the “maximum penalty”.

Prosecutors had argued that the mother-of-two should be sentenced to life in jail with no prospect of release – the harshest punishment available in Australia.

Justice Beale agreed the crimes were the worst of their kind, but said his decision to allow parole was influenced by the “harsh prison conditions” Patterson faces in jail – including 15 months spent in solitary confinement so far, and the “substantial chance” that she could face more for her safety.

The judge noted that Patterson’s reputation and the high-level of media and public interest in her case meant she would likely “remain a notorious prisoner for many years to come, and, as such, remain at significant risk from other prisoners”.

He further described Patterson’s current jail conditions in a female maximum security prison, where she spends 22 hours a day in her cell with no contact with other inmates due to her “major offender status”.

Justice Beale pointed out that the prosecution had not alleged a motive for Patterson’s crimes during the nine-week murder trial, which wrapped up two months ago, and that he would not either.

“Only you know why you committed them,” he said, in reference to the three murders and the attempted murder. “I will not be speculating about that matter.”

The judge said Patterson “showed no pity” for her victims in the days after the lunch, as those who had eaten her toxic meal fought for their lives in hospital.

“Your failure to exhibit any remorse poured salt in all the victims’ wounds,” he told the court.

Outside the court, Ian Wilkinson, the sole survivor of the fatal lunch, spoke publicly for the first time about the ordeal that tore his family apart.

He thanked the police and prosecutors who worked on the case as well as the countless medical staff who treated the victims and himself in the days after the lunch.

“I would like to encourage everybody to be kind to each other,” Mr Wilkinson said.

At a pre-sentence hearing a fortnight ago, Wilkinson described feeling “half-alive” after the death of his “beautiful wife” and losing his two best friends.

The high-level of scrutiny and interest in Patterson’s case culminated at Monday’s sentencing, with the court deciding for the first time in its history to allow a TV camera into the courtroom so that the proceedings could be broadcast live.

Previously, only in-house cameras have livestreamed sentencings.

Patterson has 28 days to lodge an appeal against her sentence, as well as the guilty verdicts for triple murder and one of attempted murder.