By Tiffanie Turnbull | BBC News, Sydney

When Dr Chris Webster saw Erin Patterson walk into a small rural hospital in Leongatha, Victoria, he felt it instantly—this woman had poisoned her family.

“I knew,” he told the BBC. “I thought, ‘Okay, yep, you did it, you heinous individual. You’ve poisoned them all.’”

Earlier that day in July 2023, Dr Webster had been treating two patients—Heather and Ian Wilkinson—for what initially appeared to be severe food poisoning. He soon learned they had attended a lunch at Erin Patterson’s home, where they ate a beef Wellington. It tasted “delicious,” Heather had said.

But everything changed when a call came in from Dandenong Hospital, where two other guests from the same lunch—Don and Gail Patterson, Erin’s in-laws—were being treated. The other doctor on the line told Dr Webster it wasn’t the meat. It was mushroom poisoning—likely from the highly toxic death cap mushroom.

Suddenly, it wasn’t food poisoning—it was a potential murder.

Dr Webster scrambled to begin life-saving treatment for the Wilkinsons and prepared them for transfer to a larger hospital for critical care. That’s when a woman rang the hospital bell, complaining of gastro-like symptoms.

Through the glass, she said her name: Erin Patterson.

“The penny dropped… it’s the chef,” Dr Webster recalled.

He brought her in and calmly informed her that they were likely dealing with deadly mushroom poisoning. When asked where the mushrooms came from, her reply was one word: “Woolworths.”

That response made the doctor’s suspicion deepen. Many locals forage wild mushrooms—admitting that wouldn’t have raised alarms. But claiming they came from a major grocery chain known for its strict food safety standards felt implausible. Even more troubling, Dr Webster noticed that Erin showed no visible concern for her relatives lying critically ill just steps away.

“She didn’t even acknowledge their presence,” he said.

Leaving Erin briefly with nurses, he returned to help transfer the Wilkinsons. As they were being loaded into an ambulance, Heather called out to thank him for his care. It was a moment Dr Webster said was painfully difficult to relive.

“She could’ve screamed at me for not figuring it out sooner. But instead, she thanked me. That was harder to accept.”

But Erin wasn’t in the hospital long. She discharged herself against medical advice, and when Dr Webster called her mobile and got no response, he contacted police.

In a call played during her trial, he calmly told the emergency operator:

“This is Dr Chris Webster from Leongatha Hospital. I have a concern about a patient who has potentially been exposed to a fatal toxin… and has just left the building.”

He spelled out her name and address. The police dispatcher was surprised:

“She just got up and left?”
“She was only here for five minutes,” Webster replied.

At trial, Erin claimed she left to feed her animals and pack a bag. She said she was shocked by what she’d been told and went home to lie down before returning to hospital.

The prosecutor challenged this, asking if leaving a hospital after being told she may have ingested a deadly poison wasn’t “the last thing you’d do.” Erin responded flatly:

“It might be the last thing you’d do. But it was something I did.”

She later returned to the hospital, where Dr Webster urged her to bring in her children, as she claimed they had eaten leftovers of the same dish.

“She was concerned they’d be scared,” Dr Webster testified.

“I said, ‘They can be scared and alive, or dead.’”

Erin claimed she wasn’t unwilling, just overwhelmed, and that Dr Webster’s tone felt like yelling. “I’ve since learnt this was his inside voice,” she told the jury.

Medical tests on Erin and her children showed no signs of mushroom poisoning, and after a precautionary 24-hour hospital stay, they were discharged.

Meanwhile, Erin was later convicted of the murders of Don and Gail Patterson and Heather Wilkinson, and the attempted murder of Ian Wilkinson, who survived after intensive treatment.

From a doctor’s gut feeling to a high-profile criminal conviction, Dr Chris Webster’s instincts and swift response played a crucial role in exposing one of Australia’s most chilling domestic crimes.