The Australian woman serving a life sentence for the mushroom murders has officially filed an appeal against her conviction.
The 51-year-old was found guilty in 2023 of murdering three relatives and attempting to murder another with poisonous mushrooms at her home in Victoria state.
Under Australian law, appealing is not an automatic right, and Patterson's legal team had to convince the Court of Appeal that there may have been legal errors in her trial.
Patterson's appeal was officially filed on Monday after the court granted her lawyers permission to challenge the sentence. The grounds for the appeal have not yet been revealed.
During the 11-week trial, Patterson maintained her innocence, arguing that it was all a terrible accident and that she did not intentionally add poisonous mushrooms to the beef Wellington meal she cooked and served for lunch.
Her in-laws, Don and Gail Patterson, both 70, and Gail's sister Heather Wilkinson, 66, died after eating the meal. Heather's husband, Ian Wilkinson, a local pastor, survived after recovering from a coma and is still battling health problems related to the poisoning.
After seven days of deliberation, the 12-member jury panel delivered a unanimous verdict – guilty on all charges.
Nine weeks of testimony gripped the court.
True crime fans were captivated by the mushroom killer case.
She was handed the longest prison sentence ever given to a female offender in Australia – a life sentence, with no possibility of parole for at least 33 years. This means Patterson will have to be over 80 years old before she is eligible to apply for parole.
She will now have the opportunity to challenge the jury's verdict.
The 28-day period for filing an appeal expired on October 6, although under a new procedural rule, legal teams were allowed an extension of time without having to give a reason, giving her lawyers more time to complete the paperwork.
Last month, prosecutors filed their own appeal against the sentence, arguing it was "manifestly inadequate".
The poisonous mushroom case attracted intense public interest, and the small town court in Morwell was besieged by media during the trial.
Over nine weeks of testimony, the jury heard evidence suggesting Patterson had collected death cap mushrooms from nearby towns and lured her victims into eating the deadly meal under the false pretense that they had cancer – before attempting to cover up her crimes by lying to police and destroying evidence.
Her estranged husband, Simon Patterson, was also invited to the lunch but cancelled at the last minute, as he suspected his wife had been trying to poison him for years.
Following the trial, it emerged that on several occasions in the past he had become so ill after eating her food that he fell into a coma, had a large section of his bowel surgically removed, and his family was twice told to say goodbye to him as he was not expected to survive.
Patterson is currently being held at a women's high-security prison in Melbourne called the Dame Phyllis Frost Centre. During sentencing, Justice Christopher Beale told the court that she spends 22 hours a day in her cell and has no contact with other prisoners due to her "high-profile offender" status. The judge stated that Patterson's notoriety and the intense media and public interest in the case meant that she would "remain a notorious prisoner for many years to come, and as such, would be at considerable risk from other inmates."