Poison Plot: How Details of Meal and Cover-Up Emerged During Trial

Several hours after a person eats death cap mushrooms and becomes violently unwell, there is a period of relief.

- Nino Bucci

They feel as if they are improving. They are not.

This pause soon gives way to "a relentlessly progressive and quite frightening rapid deterioration into multiple organ failure", the director of intensive care at Austin Health, Dr Stephen Warrillow, told Erin Patterson's triple murder trial.

"The body's different organ systems essentially shut down and the patient is extremely unwell, at a very high risk of dying."

During an extended trial that was subject to ghoulish fascination, at times it seemed almost an afterthought that Don Patterson, Gail Patterson and Heather Wilkinson died terrible deaths.

Ian Wilkinson barely escaped the same fate, but he was watching in court as Warrillow gave his evidence. About 5 metres to Ian's left was the woman on trial for trying to kill him.

There was no dispute that Patterson poisoned him and the others with death cap mushrooms, that the blame for their deaths fell at her feet. But had she meant to?

Yesterday, a supreme court jury convicted Erin Patterson of murdering her estranged husband's parents, Don and Gail Patterson, and his aunt, Heather Wilkinson. The 12-person jury also found her guilty of attempting to murder Heather's husband, Ian Wilkinson.

The difficulty in proving intent - as the defence made sure it repeatedly emphasised - was that the prosecution could not say why Patterson killed three people and tried to kill a fourth.

Despite the law being clear that no motive was required, this was no small thing for a jury: how to be satisfied beyond reasonable doubt that a mother of two children, with no criminal history, is guilty of triple murder, when nobody can tell you why she did it?

Patterson said the deaths were due to a slight reorganisation of her pantry. At some point, she put foraged mushrooms that she did not realise were death caps in the same storage container as mushrooms she bought from an Asian grocer.