Erin Patterson Mushroom Murder Case: What Happened And What The Appeals Seek

The Victorian Court of Appeal has heard Patterson’s conviction appeal and the Director of Public Prosecutions’ separate sentence appeal.

Patterson is appealing her convictions for murdering Gail Patterson, Don Patterson and Heather Wilkinson, and attempting to murder Heather’s husband, Ian Wilkinson. The DPP argues that the 33-year non-parole period imposed after her conviction was manifestly inadequate and is seeking a sentence that would leave Patterson with no possibility of parole.

The two proceedings raise separate questions: whether Patterson’s convictions should stand and whether the punishment imposed on her should be increased.

The 2023 Mushroom Lunch

In July 2023, Patterson hosted four relatives and family members at her home in Leongatha, Victoria.

The guests were Don and Gail Patterson, Gail’s sister Heather Wilkinson and Heather’s husband Ian Wilkinson. Patterson’s estranged husband, Simon Patterson, had also been invited but did not attend.

Patterson served Beef Wellingtons containing death cap mushrooms.

Gail Patterson, Don Patterson and Heather Wilkinson later died. Ian Wilkinson survived after becoming seriously ill and was hospitalised.

The prosecution case was that the poisoning was deliberate. The jury subsequently found Patterson guilty of three counts of murder and one count of attempted murder. The Supreme Court of Victoria later placed the offending in the worst category for sentencing.

Who Were The Victims?

The four people at the lunch were connected to Patterson through her former marriage.

Don and Gail Patterson were the parents of Patterson’s estranged husband, Simon. Heather Wilkinson was Gail’s sister, while Ian Wilkinson was Heather’s husband.

The sentencing court described the victims as relatives by marriage who had been good to Patterson and her children over many years.

Three died and Ian Wilkinson survived. The court recorded the severe consequences of the poisoning for Wilkinson, who required hospital treatment and suffered serious health effects.

The case therefore involved people who had been invited into Patterson’s home for what was presented as a family meal.

What Did Prosecutors Allege And What Evidence Was Presented?

The prosecution relied on toxicology, evidence concerning death cap mushrooms, digital and phone material, CCTV footage and evidence surrounding a food dehydrator, according to the trial and sentencing records.

The prosecution argued that this evidence supported its case that the poisoning was deliberate rather than accidental. The jury subsequently found Patterson guilty on all four charges.

Evidence surrounding the dehydrator was among the issues considered at trial. CCTV showed Patterson taking a dehydrator to a waste facility after the lunch, and the prosecution relied on that evidence as part of its case.

The prosecution also presented evidence concerning Patterson’s movements, communications and interactions with the victims.

The jury, rather than the sentencing judge, determined whether the charges had been proved beyond reasonable doubt. In Victoria, a criminal jury decides guilt on the evidence presented at trial.

That distinction is important now because Patterson’s appeal concerns aspects of the trial and whether legal or procedural errors affected the fairness of the proceedings.

Why Was Erin Patterson Convicted?

The jury found Patterson guilty of three counts of murder and one count of attempted murder.

The three murder convictions related to Gail Patterson, Don Patterson and Heather Wilkinson. The attempted-murder conviction related to Ian Wilkinson, who survived.

The Supreme Court’s sentencing material records the convictions and the court’s findings relevant to sentencing, including that Patterson deliberately served a meal containing death cap mushrooms.

Patterson’s lawyers now argue that several aspects of the trial caused a miscarriage of justice.

What Sentence Did The Court Hand Down?

In September 2025, Justice Christopher Beale sentenced Patterson to life imprisonment with a 33-year non-parole period. She had already spent 676 days in custody before sentencing.

The 33-year period means Patterson would not be eligible to apply for parole until she had served that minimum period.

The judge placed the offending in the worst category for murder and attempted murder. He considered the betrayal of trust, the impact on the victims and their families, the suffering inflicted on the surviving victim and the broader consequences of the offending.

The sentencing judge also considered Patterson’s prison conditions. Because of her notoriety and concerns for her safety, she had been held in continuous solitary confinement, which the judge regarded as likely to continue for the foreseeable future.

The court therefore imposed life imprisonment but fixed a substantial non-parole period rather than imposing a sentence with no possibility of parole. That reasoning is now being challenged by the prosecution.

What Is Patterson Appealing?

Patterson’s lawyers argue that several aspects of the trial caused a miscarriage of justice.

Her lawyers have challenged evidence involving phones and mobile-tower data, mushroom-related material and social-media evidence, as well as aspects of the cross-examination and the circumstances surrounding the jury’s accommodation.

The accommodation issue concerns the circumstances in which jurors were housed during the original trial. Patterson’s lawyers argue that those arrangements created an irregularity capable of affecting the fairness of the proceedings. Other grounds concern evidence and the way it was presented to the jury.

The appeal is therefore not simply a second trial over whether Patterson served poisonous mushrooms. It asks whether legal or procedural errors during the original proceedings were serious enough to justify intervention by the Court of Appeal.

Why Are Prosecutors Seeking No Possibility Of Parole?

The Victorian DPP is also appealing, but on a different question.

The prosecution argues that Patterson’s sentence was manifestly inadequate given the seriousness of the offending and is seeking a sentence that would leave her with no possibility of parole.

The DPP is not appealing the murder and attempted-murder convictions. It is challenging the punishment imposed after those convictions.

The prosecution’s sentence appeal also challenges the weight given to Patterson’s prison conditions when the 33-year non-parole period was set. The DPP argues that the seriousness of the offending should outweigh those considerations and that the sentence imposed does not adequately reflect the gravity of the crimes.

Under Victorian procedure, the DPP may appeal a sentence if it considers the sentence manifestly inadequate.

If the prosecution succeeds, the sentence can be increased. If it fails, Patterson’s existing sentence remains in place.

What Can The Appeal Court Decide?

Patterson’s conviction appeal and the DPP’s sentence appeal are separate, even though they arise from the same case and were heard together over two days.

The Victorian Court of Appeal hears criminal appeals from the Supreme and County courts. An appeal against conviction generally requires leave, while a DPP appeal against sentence is separately provided for under the court’s criminal-appeals process.

For Patterson, the Court could reject the conviction appeal, leaving the guilty verdicts in place, or allow it and make an appropriate order. Possible outcomes include a retrial or an acquittal, depending on the circumstances.

The Court can also consider whether legal or procedural errors during the original proceedings were serious enough to warrant intervention.

On the sentence appeal, the possible outcome is different. If the DPP succeeds, the sentence can be increased; if the appeal is dismissed, the existing sentence remains in place.

The two appeals could therefore produce different outcomes. Patterson could fail to overturn her convictions while the DPP succeeds in seeking a harsher sentence, or the Court could reject the prosecution’s challenge and leave the existing 33-year non-parole period unchanged.

What Happens Next?

The two-day hearing has now concluded and the Court of Appeal has reserved its decision. No date has been announced for the judgment.

Until then, Patterson’s convictions and life sentence with a 33-year non-parole period remain in force.

The Court must now decide whether the original trial contained errors serious enough to affect the convictions and whether the sentence imposed was adequate for the offending.