Convicted triple murderer Erin Patterson returned to court Wednesday to challenge her convictions for poisoning four relatives of her estranged husband with deadly death cap mushrooms.
A three-judge panel in the Victoria state Court of Appeal is considering Patterson’s two-day appeal against three murder convictions and one attempted murder conviction linked to a July 2023 lunch at her rural Leongatha home, where she served beef Wellington pastries.
Prosecutors are also contesting what they say was an overly lenient sentence. Patterson, 51, was sentenced in September last year to life in prison with a minimum term of 33 years before she can seek parole.
At Thursday’s hearing, prosecutors will argue Patterson should spend the rest of her life in prison with no possibility of parole, Prosecutor Brendan Kissane told the court.
On Wednesday, defense lawyer Richard Edney opened the appeal by arguing that a serious error occurred when jurors were sequestered in the same hotel as a police witness and members of the prosecution team.
“This was a very serious breach of sequestration,” Edney told the court.
Kissane rejected that argument, saying there was no evidence to support the claim.
“There was no actual contact between any juror and any other person,” Kissane said.
Another defense lawyer, Veronika Drago, said there was no evidence that Patterson had read online posts that reported death cap mushrooms had been seen near the towns of Loch and Outtrim.
The trial heard evidence from a telecommunications expert that Patterson’s phone connected to towers near Outtrim and Loch.
Drago said the evidence was that Patterson’s phone had possibly been in the area.
“That in and of itself, in our submission, illustrates just how dangerous and unfair that evidence was” on Patterson’s trial, Drago said.
Prosecutor Jeremy McWilliams said the evidence showed that Patterson had an opportunity to deliberately source death cap mushrooms shortly before the lunch.
Another ground for appeal was that Prosecutor Nanette Rogers’ cross-examination of Patterson over five days had been “unfair and oppressive.”
The defense team also argued that trial judge Christopher Bale had caused “unfair prejudice” by allowing evidence from Patterson’s Facebook “friends” into the trial.
Patterson’s estranged husband, Simon Patterson, was invited to the fatal lunch but did not attend.
His parents, Don and Gail Patterson, and Gail’s sister, Heather Wilkinson, died. Heather’s husband, Ian Wilkinson, spent weeks in hospital, but survived.
Patterson argued during her trial that the poisoning was an accident.
Vargo argued a miscarriage of justice occurred when the prosecution opened their case saying there was no evidence of a motive for the poisonings, then closed the case suggesting Patterson’s animosity toward her husband’s parents and the broader Patterson family was the motive.
Questioned by one of the three judges, Justice Lesley Taylor, Vargo she was not accusing prosecutors of deliberate professional misconduct.
“It is certainly not a direct allegation or suggestion of that, but what is clear in our submission from the reading of all of the material is that where things started and where it finished by the end of the prosecution case were different,” Vargo said.
If Patterson’s appeal succeeds, the judges could overturn her convictions and order a retrial.
Patterson did not attend court on Wednesday and watched the hearing by video in prison.
In pretrial testimony only made public after her trial, Simon Patterson said he suspected his wife had deliberately made him seriously ill with dishes. No poisons were ever found.
Erin Patterson was initially charged with three counts of attempting to murder him three times between November 2021 and September 2022. She had denied all charges.
Prosecutors dropped all charges relating to the husband before her trial began in April 2025.
