Australian Court Keeps Mushroom Killer's Secret Evidence Sealed Until Nov. 27

An Australian appeals court has refused to let media outlets publish a piece of secret evidence from the Erin Patterson mushroom murder case, ABC Australia reported. The judges said the material could taint any retrial if Patterson wins a last-ditch appeal to the High Court. The ban will lift on Nov. 27 unless she applies for that appeal.

What did the court decide?

Victoria's Court of Appeal declined to lift a suppression order covering one piece of evidence. The Independent reported that the court said Patterson could face unfair prejudice if potential jurors learned of it. In a partially redacted judgment published online, Justices Stephen McLeish, Lesley Taylor and Peter Kidd wrote that the evidence is nuanced and complex but would likely draw very significant publicity, creating a real risk to any future trial.

ABC said that for legal reasons it cannot report what the evidence is.

Why was the evidence never heard by the jury?

The material was expected to be part of Patterson's 2025 trial, where she was charged with murdering relatives Don Patterson, Gail Patterson and Heather Wilkinson, and with attempting to murder Ian Wilkinson. According to ABC, Justice Christopher Beale ruled midway through the trial, after further legal argument, that the evidence was inadmissible, so jurors never saw it.

After Patterson was found guilty, Beale suppressed the material while her appeal was pending. He found it would receive “massive publicity” if published, the appeal judges wrote, and would leave an “indelible impression” on potential jurors in a retrial.

What did the media argue?

Media outlets, including the ABC, asked the court to lift the order after Patterson's appeal failed last month. Their barrister, Marcus Hoyne, agreed the evidence would stay in the public's mind if published. But he argued that any retrial would be heavily delayed, and that a judge could instruct jurors about the evidence and explain why it was ruled irrelevant and inadmissible.

The judges were not persuaded. They said the publicity posed a risk to the proper administration of justice and that it would be highly undesirable for jurors to know of the evidence.

Is this a new rule for secret evidence?

No. In most legal matters, reporting restrictions end when a trial ends, which allows publicity about things the jury did not hear. The judges called this an exceptional case and stressed that their decision does not mean contentious, inadmissible evidence will automatically be suppressed in other cases.

Some other suppressed material was released last year, ABC reported. It included unproven allegations that Patterson tried to murder her estranged husband, Simon. She denied them, and prosecutors dropped them.

How did the appeal turn out for Patterson?

On Oct. 30, the Court of Appeal dismissed all seven grounds of her appeal against her convictions, the judges calling her crimes extraordinarily cold and calculated. The case involved a meal laced with death cap mushrooms in July 2023. Two of the people who ate it, Don and Gail Patterson, died, as did Gail's sister Heather Wilkinson. Heather's husband, Ian, survived after being hospitalized, according to The Independent.

Patterson had originally been sentenced to life in prison with a possible parole date after 33 years. The appeal court sided with prosecutors that this was too lenient, set aside the 33-year non-parole period and ordered life without parole. McLeish described the offending as shocking criminality, and the court said parole should not be an option. Patterson appeared by video link from the maximum security wing of Dame Phyllis Frost women's prison.

Why does it matter?

The ruling shows how courts balance open reporting against a defendant's right to a fair trial when a conviction is still being challenged. For now, the public cannot see the evidence, and the decision keeps a retrial, if one is ever granted, free of its influence.

What happens next?

Patterson has until Nov. 27 to apply for special leave to appeal to the High Court. If she does not, the suppression order lifts and the evidence can be reported. The Independent noted that legal experts say she could seek a second appeal if compelling evidence emerges that exonerates her.

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Around Prague, based on reporting by ABC News (Australia), The Independent

Cover photo: Nickbenanh / Wikimedia Commons, CC BY-SA 3.0, cropped