Foraged mushrooms, fatal doses and food binges: the week Erin Patterson told her story to triple murder trial

In Erin Patterson’s telling, the moment she realised she could be blamed for harming her in-laws came before they even died.

According to evidence Patterson gave at her triple-murder trial this week, she was in a Monash hospital room alone with her estranged husband, Simon, after their two children had left to buy food from a vending machine, when he asked her: “Is that how you poisoned my parents, using that dehydrator?”

It was 1 August 2003 – three days after Patterson served beef wellingtons to her parents-in-law, Don and Gail Patterson, Gail’s sister Heather Wilkinson, and Heather’s husband, Ian. Three of her guests died before the week was out, and Ian remained critically unwell.

Patterson, 50, is charged with murdering Don, Gail and Heather, and attempting to murder Ian. She has pleaded not guilty.

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“Did that comment by Simon cause you to reflect on what might have been in the meal?” Patterson’s lawyer, Colin Mandy SC, asked her this week.

“It caused me to do a lot of thinking about a lot of things, yeah … it caused me to reflect a lot on what might have happened.”

Patterson was discharged from hospital later that day. In her words to the court, she was starting to feel scared, responsible, frantic.

Patterson said she realised dried mushrooms from an Asian grocer, and dried mushrooms that she foraged and then dried in the dehydrator, were in a container in her pantry.

“Can you explain to us what crossed your mind then and what you were thinking about?” Mandy asked her this week.

Patterson replied: “It got me thinking about all the times that I’d used [the dehydrator] … and how I had dried foraged mushrooms in it weeks earlier, and I was starting to think, ‘what if they’d gone in the container with the Chinese mushrooms? Maybe – maybe that had happened’.

“[I felt] … scared. Responsible. Really worried because child protection were involved and Simon seemed to be of the mind that maybe this was intentional and I just – I just got really scared.”

Child protection was due to visit her Leongatha property on 2 August, the day after she was discharged.

After she drove the children to school that morning, she dumped a Sunbeam food dehydrator at a local tip. It was later found by police with her fingerprints and traces of death cap mushrooms on it.

“Child protection were coming to my house that afternoon, and I was – I was scared of the conversation that might flow about the meal and the dehydrator, and I just was – I was scared … that they would blame me for it,” Patterson said.

“For making everyone sick, and I was scared they’d remove the children.”

This, then, was Patterson’s explanation for her lies, lies the jury was told about all the way back on 30 April, the second day of the trial.

And here, also, was her explanation for the tragic and terrible accident, as described by Mandy that same day.

The question for the jury now was how to consider it: material in the prosecution and defence opening arguments is not, after all, evidence, but what each side says the evidence shows.

The prosecution must prove there was no accident: that Patterson intended to put death cap mushrooms in the beef wellingtons, and that she meant to kill or cause serious harm to her guests when she did so.

Illustration: Guardian Design

Nanette Rogers SC, for the prosecution, asked Patterson why she did not tell anyone that she had come to the realisation that death cap mushrooms might have been in the meal, nor that she might have foraged them, given she says she realised that on 1 August 2023.

In his evidence earlier in the trial, Simon denied that he had made the comment about the dehydrator to Patterson.

Rogers asked Patterson about photos found on devices seized by police that showed sliced mushrooms on shelves of the dehydrator, which had in turn been placed on electronic scales.

Dr Tom May, a mushroom expert, earlier told the trial those same photos appeared to show death caps.

Rogers asked Patterson if she was weighing them in order to calculate the fatal dose for a human.

In her opening statement, Rogers said the prosecution’s case was that Patterson invited her guests for lunch “on the pretence that she’d been diagnosed with cancer and needed advice about how to break it to the children”.

Patterson agreed she never had cancer, but said evidence the court heard from Simon and Ian regarding her telling her lunch guests she had been diagnosed was incorrect.

Rogers said in her opening that the prosecution also alleged Patterson did not consume death cap mushrooms at the lunch, and pretended she was suffering the same illness as her guests “to cover that up”, explaining “why we say she was reluctant to receive medical treatment for death cap mushroom poisoning”.

Patterson disputed this, but said she ate a significant amount of cake after the lunch – consistent with previous evidence of her having issues with binge eating going back to her 20s – and then vomited all the food from the meal “back up again”.

The prosecution also alleged Patterson did not feed the leftovers of the poisoned beef wellington to her children, which is why she was reluctant to have them medically assessed. Patterson denied she made two batches of wellingtons, saying the children just had the mushrooms and pastry removed from their servings.

Rogers also said in her opening statement that the prosecution would not be suggesting a motive in the case, and that the jury may still be unclear at the end of the case why Patterson had done what she was accused of.

“What you will have to … focus your attention on, is whether you are satisfied beyond reasonable doubt that the accused committed the charges … not why she may have done so,” Rogers said.

With Patterson in the box, however, Rogers started to focus on what Patterson really thought of her lunch guests.

Her messages to Facebook friends, and to Simon, Gail and Don, had been referred to repeatedly throughout the case, but now the person who sent them could be asked what they meant.

No, Patterson said to Rogers, the exchanges between her and her Facebook friends, which occurred at the same time as messages in a group chat with the Pattersons, did not demonstrate she was two-faced.

“You had two faces, a public face of appearing to have a good relationship with Don and Gail … and I suggest your private face was the one you showed in your Facebook message group,” Rogers said.

“Incorrect,” Patterson responded.

She denied that the way she spoke about Don and Gail on Facebook, including “this family I swear to fucking god”, wanting “nothing to do” with them, that she was “sick of this shit” and “fuck em”, was how she truly felt.

Patterson also disagreed that she never asked how any of the lunch guests were faring, despite knowing they were unwell.

Rogers, staccato, rifled through them, suggesting Patterson had not shown concern about people she said she loved.

Don was first, then Gail and Ian.

“And you never asked how Heather was going, and I assume you disagree?” Rogers asked.

“Correct,” Patterson responded.

Her evidence will continue on Tuesday.