Mushroom murderer Erin Patterson's appeal hinges on 'catastrophic' hotel mix-up with jury and prosecutors

Lawyers for Australian mushroom killer Erin Patterson have argued at her appeal hearing that her murder conviction was undermined by a "catastrophic" hotel mix-up during the trial, and called for a retrial.

Patterson is serving a life sentence after killing three relatives with a beef Wellington containing death cap mushrooms at her Victoria home in July 2023. Her victims were her in-laws Don and Gail Patterson, both 70, and Gail's sister Heather Wilkinson, 66. Her estranged husband Simon, who cancelled at the last minute, survived.

Patterson's barrister Richard Edney told the Court of Appeal in Melbourne that while jurors were deliberating their verdict, they stayed in the same hotel as members of the prosecution team, a key police witness, and journalists. He said this "undermined the integrity of the verdicts and requires the quashing of the convictions" and called for a retrial so that "justice can not only be done but be seen to be done".

Director of Public Prosecutions Brendan Kissane accepted the situation was regrettable but argued it happened "by accident" and that there was no evidence of communication between jurors and any other party.

Patterson's lawyers also challenged prosecution theories about how she sourced the mushrooms, arguing that mobile phone evidence and iNaturalist website sightings were too speculative and should not have gone before the jury.

Separately, Victoria's Director of Public Prosecutions is appealing against Patterson's 33-year parole period, calling it "manifestly inadequate".

Patterson, 51, did not attend the hearing in person, watching via video link from prison.