Erin Patterson, found guilty of murdering three members of her husband’s family and attempting to murder a fourth, faces a pre-sentence hearing on August 25. The trial revealed a complex web of evidence, including allegations of poisoning, a canceled lunch, and the involvement of multiple family members.

Allegations of Poisoning

Simon Patterson, Erin’s ex-partner, had long suspected that Erin had poisoned him on multiple occasions. He claimed that after eating meals she prepared, he fell ill four times, leading to suspicions of deliberate poisoning. During pre-trial hearings, medical expert Andrew Bersten testified that Simon’s illnesses had no identified cause, though they occurred with severe and sudden onset.

New evidence emerged in April 2025, when Crown prosecutor Nanette Rogers revealed that police had found information about the rat poison Barium Carbonate on a computer seized from Erin’s home around the time of Simon’s illness in September 2022. A supplementary report from Bersten concluded that Simon’s medical records were “consistent” with Barium Carbonate poisoning.

The Canceled Lunch

Simon had initially accepted an invitation to a lunch with Erin and her parents, Don and Gail Patterson, as well as their relatives, after a church service on July 16, 2023. However, the night before the lunch, he texted Erin to cancel, stating he felt “too uncomfortable” to attend. In his message, he wrote:

“Sorry, I feel too uncomfortable about coming to the lunch … but am happy to talk about your health and implications of that at another time if you’d like to discuss on the phone.”

Erin responded, calling his decision “really disappointing,” and expressed her efforts to prepare a special meal for the occasion. Simon did not attend the lunch, and it was later revealed that a sixth beef wellington was prepared for him in case he changed his mind.

Familial Reactions and Concerns

Simon confided in his father, Don Patterson, and his younger sister, Anna Terrington, about his suspicions that Erin had poisoned him. Don advised him not to tell too many people about his concerns, possibly to avoid creating tension within the family. Anna Terrington, though she did not recall the exact timing, said she took Simon’s concerns seriously.

Before the fatal lunch on July 29, 2023, Don and Gail Patterson had a meal at Erin’s home. Anna Terrington said her mother, Gail, later told her that Don had advised her to “stop catastrophising things.” She did not understand what this meant at the time.

Legal Proceedings and Trial Outcomes

During the trial, senior Crown prosecutor Nanette Rogers SC alleged that a sixth beef wellington was prepared for Simon in case he changed his mind about attending the lunch. Erin denied this, claiming that the steaks used were in twin packs and that she had enough ingredients to prepare an extra portion.

The prosecution’s case was that Erin had deliberately poisoned her husband’s family during the lunch on July 29. Don and Gail Patterson, as well as Gail’s sister Heather Wilkinson, died from death cap poisoning in the week following the lunch. Heather’s husband, Ian Wilkinson, survived the poisoning.

Earlier in the trial, three attempted murder charges against Erin were dropped after a pre-trial ruling that they would have to be heard as a separate trial. Prosecutors had argued that the evidence of Simon’s previous illnesses and the lunch poisonings could be combined, but the defense successfully opposed this, citing the risk of unfair prejudice.

The Court of Appeal upheld the trial judge’s ruling in April 2025, and the charges were subsequently discontinued by the Director of Public Prosecutions a week before the trial began with a jury being empanelled.

Conclusion

Erin Patterson was found guilty of murdering three family members and attempting to murder a fourth. She will face a pre-sentence hearing on August 25. The trial underscored the complex nature of the case, the emotional toll on the families involved, and the legal challenges faced by both the prosecution and defense.