What are Australia mushroom murders? Woman found guilty of killing in-laws

An Australian woman was found guilty of murder and attempted murder of her husband’s relatives, three of whom died after consuming the meal prepared by her. A 12-member jury reached the verdict after a 10-week trial, nearly two years after Erin Patterson served home-cooked beef wellingtons, which contained the toxic mushrooms, to the four guests at her home in Leongatha, Victoria, in July 2023. The 50-year-old mother of two is facing life in prison and will be sentenced later.

The shocking event had drawn attention, as the world watched the trial of the mysterious case. During the long trials, which included over 50 witnesses and eight days of Patterson’s testimony, the case witnessed several twists and turns. Meanwhile, the jury was faced with the main question: Did Patterson knowingly lace the dish with the toxic mushrooms with the intention to kill her in-laws?

What happened at lunch?

In July 2023, Patterson hosted her estranged husband’s elderly parents, Gail and Donald Patterson, his aunt, Heather Wilkinson, and his uncle, Ian Wilkinson. She served her guests homemade beef Wellington, a steak dish wrapped in pastry, usually with a paste of finely chopped mushrooms. Her husband, Simon Patterson, was also invited to the gathering, but declined because he felt “uncomfortable”.

While she admitted that the mushroom paste contained death cap mushrooms, the most lethal fungus in the world, she maintained that the dish was accidentally poisoned.

The following day, all four guests suffered gastrointestinal symptoms and were hospitalised. Later that week, three of them died from altered liver function and multiple organ failure due to Amanita mushroom poisoning. The sole survivor, who spent weeks in intensive care, testified against Erin Patterson at the Victoria state Supreme Court.

Fake medical issue

Patterson had told them that she wanted to discuss her medical issues and whether to tell her kids. In his testimony, Wilkinson said that Patterson told them that she had been diagnosed with cancer. The prosecution accused Patterson of lying, claiming her medical records did not show any such diagnosis. Later, Patterson admitted lying from the stand, saying she was too embarrassed to tell them she was considering a weight loss surgery.

‘Serious toxin syndrome’

Wilkinson and his wife also noted that while Patterson served her guests their own individual portions of the dish, her plate was of a different size and colour than the rest. The couple were admitted to the hospital after having dozens of episodes of vomiting and diarrhoea. Following suspicion, toxicologists determined that their symptoms indicated “serious toxin syndrome caused by ingestion of amanita phalloides mushrooms.”

Their condition deteriorated, after which Heather Wilkinson and Gail Patterson died on August 4, and Donald Patterson died the following day. Ian Wilkinson, the sole survivor, was extubated on August 14. He was discharged to rehabilitation on September 11.

Did Patterson get sick too?

While Patterson said that she experienced diarrhoea for several days following the lunch, there was suspicion that she had even got sick, as prosecutors argued she did not experience any symptoms of mushroom poisoning, citing medical records and testimonies of doctors. Patterson’s lawyers claimed that she had simply not eaten enough of the meal to get as sick as others. Moreover, she suggested that she got sick after eating the cake, which was brought by one of her guests.

A series of lies

Patterson acknowledged that she did not tell authorities of the possibility of death cap mushroom ingestion as her relatives lay in the hospital. Instead, she said that she had used a variety of mushrooms in the dish. When asked by the police, she also denied that she had ever foraged for mushrooms, but later admitted she had lied. She also lied about having a food dehydrator, which she had thrown out of panic following the lunch incident. The police found the appliance, and it had traces of the fatal fungi.

The police also seized a computer from her house, which revealed she had browsed a website pinpointing death cap mushrooms spotted a short drive from her house a year before the lunch. Prosecutors also accused Patterson of trying to cover her tracks in other ways, like doing a factory reset of her phone during the investigation. Photos of wild mushrooms being weighed on the dehydrator tray were also found in her camera.

Patterson and her husband

Patterson has been married to her husband, Simon, since 2007. However, following multiple splits and reconciliations, the two separated permanently in 2015. In testimony, the couple spoke about having an amicable relationship, which later deteriorated in 2022 over issues related to child support payments of their two children, of whom they share custody.

Prosecutors alleged that Patterson killed her guests on purpose due to financial tensions with her husband. She was charged with three counts of murder and one count of attempted murder.