Erin Patterson found guilty in mushroom murders case

An Australian woman was on Monday convicted of murdering three elderly relatives of her estranged husband with a meal laced with poisonous mushrooms.

Erin Patterson, 50, was charged with the murders of her mother-in-law Gail Patterson, father-in-law Donald Patterson and Gail's sister, Heather Wilkinson, and the attempted murder of Ian Wilkinson, Heather's husband.

The four gathered at Patterson's home in Leongatha, a town of about 6,000 people 135km southeast of Melbourne, where the mother of two served them a meal of individual Beef Wellingtons accompanied by mashed potato and green beans, which were later found to contain death cap mushrooms.

On Monday, the jury found her guilty of all four charges, the court heard in Morwell, a town about two hours east of Melbourne where the trial was held.

Patterson, who had pleaded not guilty to all charges and said the deaths were accidental, will be sentenced at a later date.

Jessica O'Donnell, a spokesperson for Patterson’s estranged husband Simon Patterson and his siblings, declined to comment on the ruling.

The prosecution, led by barrister Nanette Rogers, told the court Patterson had employed four major deceptions to murder her guests. She first fabricated a cancer diagnosis to lure the guests to the lunch and then poisoned their meals while serving herself an untainted portion, Rogers said.

Patterson lied that she was also sick from the food to avoid suspicion before embarking on a cover-up when police began investigating the deaths, attempting to destroy evidence and lying to investigating officers, the prosecution said.

Patterson, who said during the trial she had inherited large sums of money from her mother and grandmother, retained a four-person legal team.

She was the only witness in her defence, spending eight days on the stand, including five days of cross-examination.

Patterson told the court about a lifelong struggle with her weight, an eating disorder and low self-esteem, frequently becoming emotional as she spoke about the impact of the lunch on the Patterson family and her two children.

She had lied about having cancer to her guests because she was embarrassed to admit she was having weight loss surgery, Patterson told the court. She wanted her relatives' advice on how to tell her children about the surgery, she said.

Patterson told the court she had not become as ill as her guests because she secretly binged on a cake her mother-in-law had brought to the lunch and then made herself sick.

The 10-week trial attracted huge global interest, with local and international media descending on court 4 at the Latrobe Valley magistrate's court in Morwell, the nearest court to Patterson's home where she had requested to be tried.

State broadcaster ABC's daily podcast on proceedings was consistently among the most popular in Australia during the trial, while several documentaries on the case are in production.