The seven reasons mushroom murderer Erin Patterson wants her convictions quashed

Mushroom murderer Erin Patterson is appealing against her convictions on the grounds the jury was potentially contaminated by staying in the same hotel as prosecutors and police, and she was subjected to “unfair and oppressive cross-examination”.

Patterson’s appeal, which was filed with the Supreme Court by her defence team two days ago, also claims the prosecution seriously erred by telling the jury it did not have to prove a motive for the murders but then spent substantial time implying she was angry at the Patterson family over a child support dispute.

Patterson was convicted in July of murdering her in-laws Don and Gail Patterson, Gail’s sister, Heather Wilkinson, and attempting to kill Heather’s husband, Ian Wilkinson, with a beef Wellington lunch poisoned with death cap mushrooms. The 51-year-old was sentenced to life in prison with a non-parole period of 33 years.

The notice of appeal is also challenging the safety of the conviction on the basis that large tranches of evidence should never have been heard by the jury. This includes cell tower reports linking her to two areas in rural Gippsland where she could have picked the deadly mushrooms and posts on the iNaturalist website of death cap sightings in Outtrim and Loch that suggested she knew where to go.

All told, Patterson’s defence lawyers at Doogue and George have presented seven grounds for appeal.

In the days after her conviction in July, The Age revealed the Juries Commissioner had opened an investigation into the circumstances which saw the Patterson jury sequestered during its deliberations in the same small-town hotel as the homicide squad, prosecutors and the media.

The potentially compromising arrangement was not disclosed to trial judge Christopher Beale for nearly five days, when staff from the Office of Public Prosecutions and Victoria Police had left the hotel.

The investigation hit a major stumbling block after CCTV footage from during the jury’s stay in the hotel was accidentally erased.

Victoria Police and the OPP have strenuously denied they did anything inappropriate. But the situation has been raised as the first point of appeal for Patterson.

“A fundamental irregularity occurred while the jury were sequestered that has fatally undermined the integrity of the verdicts and requires the quashing of the convictions and an order for a re-trial so that justice cannot only be done but be seen to be done,” the first ground reads.

The defence is also arguing that Beale “erred” when ruling out the admission of photos and videos that were found on Patterson’s devices that could have backed her claims of being a mushroom forager.

“The ‘Facebook evidence’ – including the evidence from Facebook ‘friends’ and Facebook messages - should not have been adduced in the applicant’s trial as the evidence was not (i) relevant or (ii) the probative value of that evidence was outweighed by its unfair prejudice and the admission of that evidence occasioned a substantial miscarriage of justice,” the notice of appeal said.

The other grounds of appeal claims that during eight days in the witness box, Patterson was grilled unfairly by prosecutors.

“A substantial miscarriage of justice has occurred because of unfair and oppressive cross-examination of the applicant,” court documents state.

The jury heard evidence from several of Patterson’s former online friends that she was angry at her husband, Simon, and his parents about how they had managed a dispute in 2022 over child support for Simon and Erin’s children.

The appeal documents claim prosecutors used these messages to imply to the jury that there was a motive for Patterson arranging the lethal lunch.

“A substantial miscarriage of justice occurred because despite opening the case for the prosecution on the basis that there was no evidence of motive, the prosecution in its closing address changed its case by implying that there was, in fact, a motive for murder.”

It is understood that Patterson’s tilt at the Court of Appeal is being funded by Legal Aid after her $1 million home in Leongatha was frozen by authorities ahead of possible compensation claims by the victims.

Patterson has always maintained her innocence and told the jury the deaths were a terrible accident.

Patterson’s estranged husband, Simon – the son of Don and Gail Patterson – was invited to the deadly lunch but cancelled the evening before.

Last month, the Director of Public Prosecutions filed a separate appeal with the court, seeking a harsher sentence for Patterson and arguing that she should never be released from custody.

The sentencing appeal, filed by Acting Director of Public Prosecutions Diana Piekusis, KC, contends that the judge made an error in the sentence imposed on Patterson and that a harsher one should be made.

In the paperwork released to the media, Piekusis said the appeal was “in the public interest”.

Patterson’s sentence makes her one of Victoria’s longest-serving female inmates. She will have just turned 82 before she is eligible for parole in 2056.

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