Erin Patterson's mushroom murder trial takes the jury on a tour, from beef Wellington to biochemistry

Australia Broadcast Center

16-05-2025

For 13 days, jurors in the Erin Patterson trial have been parked inside the courtroom.
Even though they haven't moved from their seats, the evidence has taken them through homes, hospitals, scientific labs, a landfill and the wilderness.
An early stop was Ms Patterson's home, where a family meal took place on July 29, 2023. Ian Wilkinson reconstructed the day for the jury. He was one of four guests who sat down with Ms Patterson, where they engaged in small talk, said prayers and ate a beef Wellington containing mushrooms.
Then, the jury was walked through hospital waiting rooms and wards. A cast of doctors, including Chris Webster, Mark Douglas, Laura Muldoon, Varuna Ruggoo and Andrew Bersten, described the scramble to understand how the lunch guests became so terribly sick.
Don and Gail Patterson and Heather Wilkinson didn't survive.
Enter Professor Dimitri Gerostamoulos, who invited the jury into the Victorian Institute of Forensic Medicine. There, lab tests confirmed a toxic twist: death cap mushroom toxins were found in human samples and beef Wellington leftovers pulled from Ms Patterson's bin.
Darren Canty took jurors to the local landfill to find a food dehydrator that was dumped by Ms Patterson days after the lunch.
The jurors' attention was drawn to the possible sources of the poisonous mushrooms in the dish. Ms Patterson said she used mushrooms from a supermarket and an Asian grocer, but other investigators asked if they had come from somewhere else.
Mycologist Tom May led the jury on a tour of Victoria and the world, showcasing the many places where deadly — and perfectly safe — wild mushrooms grow.
Dr May provided a fungal masterclass, explaining death cap mushrooms also go by their scientific name, Amanita phalloides. Brown, white, or with a hint of green, these mushrooms grow near oak trees and always have white gills and a cup at the base of their stems, he said.
Lookalikes in the wild could make identifying Amanita phalloides a challenging task, though. Sometimes, the court heard, Amanita phalloides shared characteristics with Oudemansiella gigaspora, Volvopluteus gloiocephalus, Chlorophyllum brunneum, Amanita cheelii or mushrooms from the genus Armillaria group.
"If you're going to collect wild fungi, you really have to get to know the features of mushrooms in general," Dr May said.
"You need to be able to identify the toxic species as well as the edible species."
Professor Gerostamoulos was called to the stand to simplify a series of toxicology reports.
He explained that he was on the hunt for alpha and beta amanitins, toxins found in death cap mushrooms. Just 50 grams could be lethal to a 70-kilogram human, he said, causing symptoms of diarrhoea and vomiting that escalated to organ failure and potential death.
These amanitins were found in beef Wellington leftovers, the dehydrator and in human samples from Don Patterson and Ian Wilkinson, he said.
They were not detected in Erin Patterson, or the bodies of Gail Patterson and Heather Wilkinson.
When it came to medical evidence, the jurors were given a glossary to make sense of it all, allowing them to understand terms like N-acetylcysteine, haemoglobin, creatinine and fibrinogen.
By Friday afternoon, the jury was hearing about the DNA barcoding of mushroom species. Prosecutor Nanette Rogers SC took the court to a series of test results, outlined on tables 1, 2 and 4.
"There's no table 3?" Justice Christopher Beale asked.
"No, there's no table 3," Ms Rogers replied. "It's a bit too technical and not terribly relevant in terms of — "
"That's fine," the judge interjected. "We don't need an explanation."
Ms Patterson has pleaded not guilty to murder and attempted murder charges, arguing that what happened to her lunch guests in 2023 was a terrible accident.
The jury's tour may be nearing its end, but there are still more points of interest for them to visit next week. After the evidence, they will be sequestered to a hotel while considering their verdicts.
The final destination will be the jury box: the place where they announce if Erin Patterson is guilty or acquitted.