The Australian woman convicted of killing three relatives with death cap mushrooms is fighting to overturn her life sentence, arguing jurors were housed in the same hotel as a police witness and members of the prosecution team during her trial.
Erin Patterson, 51, appeared via video link from prison as her defense team opened a two-day appeal before Victoria's Court of Appeal in Melbourne. Barrister Richard Edney told the three-judge panel that a "catastrophic" decision to place sequestered jurors in a hotel alongside a police witness, journalists, and solicitors from the Office of Public Prosecutions amounted to a fatal breach, one serious enough to require the convictions be thrown out and a new trial ordered.
Patterson was convicted in July 2025 of three counts of murder and one count of attempted murder for a beef Wellington lunch she served at her home in Leongatha, a small town in the Australian state of Victoria, on July 29, 2023. Her former in-laws Gail and Donald Patterson and Gail's sister Heather Wilkinson all died in hospital within days. Heather's husband, Ian Wilkinson, a local pastor, survived.
A judge sentenced Patterson to life in prison with a minimum of 33 years before she could apply for parole. She maintains she unknowingly used foraged death cap mushrooms in the meal.
Edney's central argument targets what happened while the jury was sequestered during deliberations. He told the court that jurors were placed in a hotel that also housed a police witness, prosecution lawyers, and members of the media, a setup he called a serious breach of sequestration rules designed to keep jurors isolated from outside influence.
Edney told the court:
"This was a hotel with windows, with common areas and the reasonable possibility cannot be excluded that the jurors sighted the informant or sighted solicitors from the Office of Public Prosecutions."
He argued the arrangement "fatally undermined the integrity of the verdicts" and asked the panel to quash the convictions and order a retrial "so that justice can be done."
Justice Peter Kidd pushed back immediately. "If they did view or see the practitioners, so what?" Kidd asked, challenging Edney to explain what concrete harm mere proximity caused.
Prosecutor Brendan Kissane offered a blunter rebuttal. He told the court that "there was no actual contact between any juror and any other person", drawing a line between physical proximity and the kind of improper communication that would actually taint a verdict.
The hotel issue was not the only ground for appeal. Edney also challenged the prosecution's use of two pieces of evidence that helped place Patterson near wild death cap mushroom sites: data from iNaturalist, a nature-identification website where users log mushroom sightings, and mobile phone tower records that prosecutors said put Patterson's phone near two locations close to her home where death caps had been spotted.
The defense argued these data points were unreliable or improperly admitted. Patterson's team also raised concerns about allegedly unfair cross-examination during the trial, prejudicial Facebook messages shown to the jury, and what they described as the prosecution shifting its theory of motive between opening and closing statements, telling jurors one thing at the start and something different at the end.
The sentencing judge had addressed the sourcing question directly, stating it did not necessarily matter where Patterson obtained the mushrooms because it was "abundantly clear" she had sourced them. That finding now sits at the center of the defense's challenge.
Patterson is not the only party appealing. In a move that underscores how seriously Australian authorities treated this case, prosecutors filed their own appeal arguing that the 33-year minimum sentence was too lenient. They want Patterson locked up for the rest of her life with no possibility of parole.
The prosecution described the non-parole period as "manifestly inadequate" and argued that the sentencing judge's reasoning was "infected" by an erroneous finding about solitary confinement conditions Patterson faced in custody. Prosecutors contend the original sentence failed to reflect the gravity of three premeditated killings and one attempted murder.
So both sides walked into the Melbourne courtroom seeking opposite outcomes, Patterson's team asking for a do-over, and the government asking for a sentence with no exit.
The July 2023 lunch was not the first time suspicion fell on Patterson. Police have alleged she may have attempted to poison her ex-husband, Simon Patterson, on three separate occasions between 2021 and 2022. Simon previously wrote about a near-fatal illness during that period that left him in a coma for 16 days. Doctors advised his family to prepare for the worst.
Patterson was originally charged with three counts of murder and five counts of attempted murder, the additional charges related to the alleged earlier poisoning attempts against Simon. But when the trial began on April 29, 2025, prosecutors dropped the three attempted murder charges connected to Simon without public explanation.
The case that went to the jury focused on the 2023 lunch. Ian Wilkinson, the sole survivor, testified that Patterson served her guests individual portions of the beef Wellington, separate from her own. Gail Patterson, Donald Patterson, and Heather Wilkinson were rushed to the hospital the next day. All three died within six days. Death cap mushroom symptoms can begin within hours of ingestion, and the toxin attacks the liver with devastating efficiency.
Police searched Patterson's home from August 5 through August 7, 2023, and she became an official suspect. CCTV footage captured her traveling to a local dump and disposing of a food dehydrator, a detail prosecutors highlighted at trial. She was arrested and charged in November 2023, pleaded not guilty in May 2024, and went to trial the following spring.
The jury convicted her on July 7, 2025. Sentencing came two months later.
The appeal now rests with the three-judge panel. Patterson's team needs to convince them that the sequestration breach, the evidentiary challenges, or the alleged prosecutorial inconsistencies, individually or together, amount to a substantial miscarriage of justice serious enough to warrant a new trial.
Justice Kidd's pointed question about the hotel proximity suggests at least one member of the panel is skeptical that seeing a prosecutor through a hotel window, without any actual contact, rises to the level of jury contamination. The prosecution's position, that no juror communicated with anyone outside the jury, draws a clear factual line the defense has not yet crossed with evidence of actual contact or influence.
If the appeal fails, the prosecution's cross-appeal for a life-without-parole sentence could still succeed, leaving Patterson worse off than before she challenged her conviction.
Three people sat down to a family lunch and never came home. The woman who cooked the meal says it was an accident. A jury said otherwise. Whether that verdict survives may now hinge on a hotel booking, and whether sharing a lobby counts as corruption or coincidence.
