Lawyers for Erin Patterson, the Australian woman serving a life sentence for poisoning three relatives and attempting to kill a fourth with death cap mushrooms in 2023, argue the trial’s integrity was compromised by a series of issues. Among them was a hotel mix-up that allowed the jury to stay in the same location as the prosecution team, a key police witness, and journalists during deliberations.

Hotel Mix-Up and Trial Irregularities

According to court documents, Patterson’s barrister, Richard Edney, described the situation as ‘catastrophic’ and argued it ‘undermined the integrity of the verdicts and requires the quashing of the convictions.’ He called for a retrial so ‘justice can not only be done but be seen to be done.’

Victoria’s Director of Public Prosecutions, Brendan Kissane, acknowledged the mix-up was regrettable but denied it was intentional. He stated the issue was whether there was communication between the jury and others, and that ‘the evidence as it stands points towards there being no communication.’

Speculative Evidence and Excluded Material

Another key argument from Patterson’s defense team was that some of the prosecution’s evidence was too speculative; During the trial, prosecutors claimed Patterson had located death cap mushrooms after two sightings were reported on the citizen scientist site iNaturalist. Her phone was also connected to cell towers in both areas.

Patterson’s lawyer, Veronika Drago, accused the prosecution of ‘turning nothing into something,’ stating that the mobile phone evidence ‘only possibly’ showed where she had been; there was no evidence, she said, that Patterson had accessed the iNaturalist posts. She added that the evidence’s value ‘was outweighed by its unfair prejudice.’

Crown prosecutor Jeremy McWilliams defended the use of the mobile phone tower expert, arguing that the jury needed to determine whether Patterson had the opportunity to source the mushrooms as alleged.

Additional Trial Issues and Parole Dispute

Patterson’s legal team also raised concerns about Facebook messages she sent months before the lunch, in which she criticized her estranged husband Simon and his parents. They claimed the messages were irrelevant and should not have been introduced in court.

Defence lawyers further criticized the cross-examination of the chief prosecutor, Dr. Nanette Rogers, calling it ‘protracted and aggressive’ and ‘doused with impermissible conduct.’ They also claimed the closing address by prosecutors during the trial was ‘problematic,’ with 35 complaints identified.

Appeal judge Justice Peter Kidd asked why these issues were not raised during the trial. Richard Edney responded that the defense lawyers were under pressure at the time and that his team had identified the issues ‘when the dust [had] settled from the trial.’

In court documents filed ahead of the appeal, prosecutors maintained that ‘guilty verdicts were inescapable,’ citing the lunch invitation, the serving of Patterson’s meal on a different plate, and the medical outcomes for the victims. They also noted the ‘extensive array of incriminating conduct’ that pointed to a deliberate act of poisoning.

Prosecutors will continue to dispute the appeal arguments on Thursday, and they are also appealing against the 33-year parole period set by the judge, calling it ‘manifestly inadequate’ and ‘inappropriate.’

The three appeal judges are expected to reserve their decision, meaning it could take several weeks before a ruling is announced.