Australian mushroom killer Erin Patterson has launched an appeal against her convictions, claiming a serious administrative error during her trial compromised the jury’s independence and potentially invalidated the verdict.
Patterson, 51, is serving a life sentence for murdering three relatives and attempting to kill another after serving them a beef Wellington containing poisonous death cap mushrooms at her home in Victoria in 2023.
Her legal team told the Court of Appeal in Melbourne that jurors were accommodated at the same hotel as members of the prosecution, a major police witness and several journalists while considering their verdict.
Defence barrister Richard Edney described the arrangement as a “catastrophic” failure that damaged confidence in the proceedings.
He argued that the convictions should be overturned and that a fresh trial should be ordered to ensure the legal process was both fair and publicly credible.
Victoria’s Director of Public Prosecutions Brendan Kissane acknowledged the incident was regrettable but said it appeared to have occurred unintentionally.
He argued that there was no indication the jurors had communicated with anyone connected to the case.
According to the prosecution, the central question was whether any contact actually occurred.
If there had been no communication, Mr Kissane argued, the hotel arrangement did not amount to a serious legal breach capable of overturning the verdict.
Patterson’s lawyers are also challenging several aspects of the evidence presented at the original trial.
One disputed issue concerns claims that she deliberately searched for death cap mushrooms after reports of the fungi appeared on the citizen-science platform iNaturalist.
Prosecutors previously told jurors that Patterson’s mobile phone had connected to telecommunications towers in locations where death cap mushrooms had reportedly been spotted.
Defence lawyer Veronika Drago argued that the phone records merely suggested Patterson might have been in those areas.
She said there was no proof that her client had viewed the online mushroom reports and accused prosecutors of building a case around assumptions rather than established facts.
The prosecution rejected that argument, maintaining that specialist evidence about mobile-phone tower connections was relevant because it could help establish whether Patterson had an opportunity to obtain the poisonous mushrooms.
Her lawyers have separately questioned the admission of private Facebook messages written by Patterson months before the fatal gathering.
The messages contained harsh comments about her estranged husband Simon Patterson and his parents, Don and Gail.
They also criticised the conduct of lead prosecutor Nanette Rogers during cross-examination, describing parts of the questioning as excessively aggressive and inappropriate.
The defence further identified 35 concerns about the prosecution’s closing submissions at the original trial.
Justice Peter Kidd questioned why some of the alleged problems had not been raised before the verdict.
Mr Edney responded that the original defence lawyers had been operating under intense pressure and that further concerns became apparent only after the proceedings had concluded.
Prosecutors have maintained that the evidence against Patterson was overwhelming and that the guilty findings were unavoidable.
They pointed to the circumstances surrounding the invitation to lunch, the fact that Patterson was served food on a separate plate, the contrasting medical consequences suffered by her and the other diners, and what they described as a broad pattern of incriminating behaviour.
Patterson’s victims were her former parents-in-law, Don and Gail Patterson, both aged 70, and Gail’s sister, Heather Wilkinson, 66.
Heather’s husband, Ian Wilkinson, survived the meal and attended the appeal hearing.
Patterson’s estranged husband Simon was also not in court.
He had been expected to join the lunch but withdrew shortly beforehand, partly because he believed Patterson had previously attempted to poison him.
Patterson did not appear physically before the judges, instead following proceedings through a video connection from prison.
The prosecution has brought a separate challenge against her sentence.
Patterson currently becomes eligible to seek parole after serving 33 years, but prosecutors argue that period is far too short and that the original judge should not have imposed a fixed minimum term.
The appeal hearing is continuing, with prosecutors expected to respond further to the defence arguments before the court considers the sentence challenge.
All three appeal judges are expected to preserve their ruling, interpreting a decision may not be delivered for several weeks.
By: Magdalene Agyeiwaa Sarpong