SYDNEY: An Australian court will on Wednesday (Aug 19) begin hearing the appeal of a woman convicted of murdering three of her estranged husband's relatives with a meal laced with deadly mushrooms.

Erin Patterson, 51, was convicted last year of murdering the three elderly in-laws by feeding them Beef Wellington laced with toxic death cap mushrooms, in a case that gripped the country.

Patterson was sentenced to life in prison with a non-parole period of 33 years, one of the longest sentences ever given to a woman in Australia. 

She maintained her innocence throughout the trial, saying the deaths were accidental.

Patterson is appealing on several grounds, including that various pieces of evidence should not have been introduced to the trial, that she suffered unfair cross-examination, and that an error that led to the jury being housed at the same hotel as some members of the media prejudiced the outcome.  

Victoria's Court of Appeal in Melbourne will also hear a separate appeal from prosecutors, who say Patterson's sentence is inadequate. 

A jury found Patterson lured her mother-in-law Gail Patterson, father-in-law Donald Patterson and Gail's sister Heather Wilkinson to a 2023 lunch at her home in Leongatha, a town of about 6,000 people, some 135km south-east of Melbourne, and fed them the poisoned meal. 

She was also found guilty of the attempted murder of Ian Wilkinson, Heather's husband, who survived the lunch.

The 11-week trial in the nearby country town of Morwell drew global interest, while the case has inspired several podcasts and books.