Erin Patterson appeals mushroom murder conviction

Australian woman Erin Patterson is set to launch an appeal in Melbourne on Wednesday against her conviction in a triple-murder case over a beef Wellington lunch laced with death cap mushrooms.

Patterson, 51, was found guilty last year of murdering her husband Simon Patterson's parents, Don and Gail Patterson, and his aunt Heather Wilkinson, at her home in Leongatha, Victoria, in 2023. She was also convicted of attempting to murder Heather's husband, Ian Wilkinson, who survived after weeks in hospital.

A judge sentenced Patterson to life imprisonment with eligibility for parole after 33 years. Three Court of Appeal judges in Melbourne are due to hear both her attempt to overturn the conviction and a prosecution appeal seeking a stiffer sentence.

Patterson argues that the trial involved several counts of “substantial miscarriage of justice”. Her lawyer says the trial judge wrongly allowed some evidence relating to Facebook messages, cell towers and death cap mushroom sightings, and wrongly excluded evidence about mushroom images on a memory card found in Patterson's home.

Her lawyer also argued that a “fundamental irregularity” while the jury was sequestered “fatally undermined the integrity of the verdicts”, without giving further details. Patterson's solicitor also accused prosecutors of an unfair cross-examination during the trial.

Before hearing the arguments in detail, the Court of Appeal judges must decide whether Patterson has grounds to challenge her conviction. Prosecutors say the sentencing judge was wrong to treat the chance that Patterson would spend years in solitary confinement as a reason for the 33-year non-parole period.