A suburban Australian mom is standing trial on charges of poisoning several of her estranged husband's relatives with death cap mushrooms at a home-cooked meal — killing three of them — in a case that has made headlines around the world.
The case against Erin Patterson opened in the Victoria state Supreme Court on Tuesday, and is expected to take about six weeks.
Patterson, 50, is accused of putting death cap mushrooms — which are among the most poisonous in the world — in a beef Wellington dish she served to her guests at a July 2023 lunch at her home in Leongatha, a town of less than 6,000 people some 85 miles from Melbourne.
Prosecutors say Patterson, who was separated from but on good terms with her husband Simon Patterson, invited his parents, aunt and uncle over for an adults-only lunch, ostensibly to discuss medical issues she was facing. Simon had declined the invitation.
All four of Patterson's lunch guests were hospitalized with gastrointestinal symptoms the day after the meal. Three of them died the following week, all from altered liver function and multiple organ failure due to Amanita mushroom poisoning.
Prosecutors accuse Patterson of lying about a cancer diagnosis as a pretense for the lunch, deliberately poisoning her guests, not eating the same dish as them and pretending to suffer similar symptoms afterward as an attempted cover-up.
"You do not have to be satisfied what the motive was or even that there was one," prosecutor Nanette Rogers told the jury on Wednesday. "The prosecution will not be suggesting that there was a particular motive to do what she did."
Patterson has pleaded not guilty to three counts of murder and one count of attempted murder.
Patterson has repeatedly denied deliberately poisoning her guests. Her legal team says she ate some of the meal herself and did genuinely get sick, just not as severely as the others at the table.
"The defense case is that she didn't intend to cause anyone any harm on that day," her lawyer, Colin Mandy, said in his opening statement. "The defense case is that what happened was a tragedy and a terrible accident."
Mandy said Patterson admits to lying to police on two instances in the aftermath of the lunch: about owning a food dehydrator and foraging for mushrooms. He said she admits to having foraged for mushrooms, but "denies that she ever deliberately sought out death cap mushrooms."
He said Patterson panicked after the lunch, not because she knew she was guilty of murder — as the prosecution argues — but "because she was so overwhelmed by the fact that these four people had become so ill because of the food that she'd served to them."
"Is it possible that people might do and say things that are not well thought out and might, in the end, make them look bad?" he added. "Is it possible that a person might lie when they find out that people are seriously ill because of the food that they've served up? Those are important issues in this case."
The case is so high-profile that the 15-person jury — including three alternates — will be sequestered during deliberations "to protect them from any interference or outside pressure … and to safeguard the integrity of their verdicts," Justice Christopher Beale said on the first day.
Beale warned that the case is "likely to continue to attract a high level of media attention," and urged jurors to consider only the evidence presented at trial, "using your head, not your heart."
Here's a guide to the case.
What was the Pattersons' relationship?
Erin and Simon Patterson met while working at the local city council, and got married in 2007. In the first days of the trial, Simon testified that Erin — who previously worked as an air traffic controller — took online classes and mostly worked as a homemaker during their marriage.
As he explained, the two split up and reconciled multiple times over the years before permanently separating in 2015, when she moved out. He described their relationship as strained toward the end, but friendly "most of the time."
The two shared custody of their two children, saw each other at church and even went on local and overseas family trips together.
Patterson also remained on amicable terms with her in-laws. Simon said Patterson and his parents loved each other, noting she was especially close with Don, a retired schoolteacher with whom she shared a love of science.
However, Rogers, the prosecutor, said Simon noticed a "sustained change" in his relationship with Patterson in 2022: Patterson apparently said she would need to seek child support from him, which he accepted. Their communication declined from that point on over issues related to child support payments, such as school fees, Rogers said.
Simon testified on Friday that they discussed the idea of bringing in a mediator in December 2022, saying that "from my point of view, Erin was being extremely aggressive."
Who was — and wasn't — at the lunch?
In July 2023, Patterson invited Simon and several of his relatives over for lunch: his parents, Gail and Donald Patterson, both 70, as well as Gail's sister, Heather Wilkinson, 66, and her husband Ian Wilkinson, 68.
Patterson said the purpose of the lunch was to discuss some medical issues she was facing and seek advice on how to break it to her kids, according to prosecutors — who say this was a pretense for the adults-only meal. She dropped the two, ages 9 and 14, off for lunch and a movie with a friend before her guests came over.
Roger said the Wilkinsons were surprised by the invitation because they hadn't yet been to Patterson's house, where she had moved the previous year. Simon testified that it was "very rare" for his wife to invite people over, and that family gatherings usually happened at other relatives' homes.
Simon texted Patterson the day before the lunch, saying he felt too uncomfortable to attend but was willing to discuss her health issues over the phone. Patterson responded in a text that Simon read from the stand on Thursday. In it, she said she was disappointed and hoped he would change his mind.
"I've spent many hours this week preparing lunch for tomorrow which has been exhausting in light of the issues I'm facing and spent a small fortune on beef eye fillet to make beef Wellingtons because I wanted it to be a special meal, as I may not be able to host a lunch like this again for some time," Patterson wrote. "It's important to me that you're all there tomorrow and that I can have the conversations that I need to have."
What happened at lunch?
Prosecutors say Patterson showed her guests around before serving them at the dining room table.
She placed individual beef Wellingtons — a steak dish wrapped in pastry, usually with a paste of finely chopped mushrooms — along with mashed potatoes and green beans on four large, gray dinner plates and one smaller, lighter-colored plate, according to Ian Wilkinson. Patterson ate off the smaller plate.
Prosecutors say the Wilkinsons finished their portion, while Gail ate approximately half and gave the rest to her husband Donald.
"There was banter amongst them about how much they'd eaten," Rogers said.
After the meal, Patterson told the group that she had been diagnosed with cancer after noticing a bump on her elbow, and asked for advice on whether to tell her kids. The group had a discussion and prayed for her.
What happened after lunch?
According to prosecutors, the elder Pattersons and Wilkinsons started to feel sick that evening, with diarrhea and vomiting throughout the night. The couples realized they had the same symptoms after they talked on the phone the next morning.
The Pattersons called an ambulance to take them to a hospital, while Simon Patterson took the Wilkinsons to another hospital, because of capacity issues. He testified that during this time, Heather Wilkinson raised the subject of the different plates at lunch.
He said that his aunt said something to the effect of: "Is Erin short of crockery? Is that why she would have this different kind of colored plate that she served herself with?" He replied at the time that Patterson didn't have many matching plates and might have just run out.
The patients were able to talk about their experience immediately after being admitted on July 30. Simon said his dad, Donald, told him about Patterson's cancer diagnosis from his hospital bed. Donald was also able to give his medical history and recount the lunch to doctors, who grew concerned that gastroenteritis was not the sole cause of his symptoms.
Multiple doctors and toxicologists discerned that their symptoms were indicative of "serious toxin syndrome caused by ingestion of amanita phalloides mushrooms," also known as death cap mushrooms.
Prosecutors say the patients were not immediately given the antidote because there was a lack of evidence to confirm that's what they had ingested, and their conditions deteriorated over the following days even as they were treated. Doctors concluded that the illness was "unsurvivable" for Heather Wilkinson, Donald Patterson and Gail Patterson.
Heather Wilkinson and Gail Patterson died on Aug. 4, and Donald Patterson died the following day. Ian Wilkison, the sole survivor, was extubated on Aug. 14 and discharged to rehabilitation on Sept. 11.
How did Erin Patterson react?
Accounts from prosecutors, police and Simon Patterson paint a picture of Erin Patterson's behavior in the hours and days after the lunch turned tragic.
Simon said the first he heard of her feeling unwell was the following morning, when she said she'd had diarrhea since the previous night. By that point, seeing how his relatives were faring, he urged her to go to the hospital.
Prosecutors say Patterson was admitted to urgent care when the hospital learned she had been at the lunch, but that she was adamant she would not stay. She initially resisted treatment and at one point walked out against medical advice.
Patterson also pushed back against the idea of bringing her kids to the hospital, which doctors recommended after learning that they had eaten leftovers.
Patterson said she had scraped off the pastry and mushrooms because they didn't like the vegetable. Rogers said doctors remembered Patterson becoming emotional when asked to bring her kids in, saying they didn't have symptoms and she didn't want to take them out of school.
"They did not eat the mushrooms," a doctor recalled her saying. "I just don't want them to be panicked and stressed."
Simon testified that he brought the kids to the hospital, where they were kept overnight but found not to be ill. He testified on Friday that Patterson "never actually asked" about how his hospitalized relatives were doing.
According to Rogers, Patterson's doctors determined she was "moderately dehydrated and appeared to have a gastrointestinal-type illness" — but had "no clinical or biochemical evidence of amanita poisoning or other toxicological substance ingestion." She was discharged on Aug. 1.
Much later, prosecutors had an intensive care specialist, Andrew Bersten, review Patterson's medical files. They said Bersten saw no evidence that she suffered an acute illness on July 30, or that she had been diagnosed with cancer in mid-2023 as she claimed. The Victorian Cancer Registry — to which diagnoses are legally required to be reported — also said it has no record of it.
What do we know about the mushrooms?
Death cap mushrooms — Amanita phalloides — are responsible for 90% of deaths by fungus, "with half a cap or even less enough to kill a person," according to the U.K.'s Woodland Trust.
The Victorian government says symptoms — including diarrhea, vomiting and stomach cramps — typically occur six to 24 hours after consumption, and can be fatal within 48 hours. The mushrooms are found in Europe, Australia and North America, usually in temperate forests or urban areas with exotic trees.
In April 2023, just months before Patterson had her relatives over for lunch, the Victoria Department of Health issued an advisory warning that death cap mushrooms were growing in the state.
That very month, prosecutors say, a local pharmacist noticed death cap mushrooms growing under oak trees during a walk in the nearby township of Loch, and documented them on a naturalist website.
In April, Patterson allegedly purchased an electronic food dehydrator and — according to location data from her seized phones — and traveled to the area of Loch. But in interviews with police, she denied owning a dehydrator and foraging for mushrooms.
In the immediate aftermath of the incident, Patterson told doctors and investigators that she had used two kinds of mushrooms for her dish: fresh from the grocery store and dried from a Chinese grocer in the area, though she couldn't remember which one.
As part of its investigation into the incident, the Department of Health checked all Asian grocery stores in the surrounding suburbs. Prosecutors say the health department was "unable to identify any store in the suburbs … that sold mushrooms as described by" Patterson.
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