MELBOURNE, Australia  — Australian woman Erin Patterson was found guilty Monday of murdering three of her estranged husband’s relatives by deliberately serving them poisonous mushrooms for lunch.

The jury in the Supreme Court trial in Victoria state returned a verdict after six days of deliberations, following a nine-week trial that gripped Australia. Patterson faces life in prison and will be sentenced later, but a date for the hearing hasn’t yet been scheduled.

Patterson, who sat in the dock between two prison officers, showed no emotion but blinked rapidly as the verdicts were read.

Three of Patterson’s four lunch guests — her parents-in-law Don and Gail Patterson, and Gail’s sister Heather Wilkinson — died in the hospital after the 2023 meal at her home in Leongatha, at which she served individual beef Wellington pastries containing death cap mushrooms.

She was also found guilty of attempting to murder Ian Wilkinson, Heather’s husband, who survived the meal.

It wasn’t disputed that Patterson served the mushrooms or that the pastries killed her guests. The jury was required to decide whether she knew the lunch contained death caps, and if she intended for them to die.

The guilty verdicts, which were required to be unanimous, indicated that jurors rejected Patterson’s defense that the presence of the poisonous fungi in the meal was a terrible accident, caused by the mistaken inclusion of foraged mushrooms that she didn’t know were death caps.

Prosecutors didn’t offer a motive for the killings, but during the trial highlighted strained relations between Patterson and her estranged husband and frustration that she had felt about his parents in the past.

The case turned on the question of whether Patterson meticulously planned a triple murder or accidentally killed three people she loved, including her children’s only surviving grandparents. Her lawyers said she had no reason to do so — she had recently moved to a beautiful new home, was financially comfortable, had sole custody of her children and was due to begin studying for a degree in nursing and midwifery.

But prosecutors suggested Patterson had two faces — the woman who publicly appeared to have a good relationship with her parents-in-law, while her private feelings about them were kept hidden. Her relationship with her estranged husband, Simon Patterson, who was invited to the fatal lunch but didn’t go, deteriorated in the year before the deaths, the prosecution said.

The individual beef Wellington pastries Patterson served her guests were a point of friction in the trial because the recipe she used contained directions for a single, family-sized portion. Prosecutors said that she reverted to individual servings, so she could lace the other diners’ portions, but not her own, with the fatal fungi — but Patterson said that she was unable to find the correct ingredients to make the recipe as directed.

Nearly every other detail of the fateful day was scrutinized at length, including why Patterson sent her children out to a film before her guests arrived, why she added additional dried mushrooms to the recipe from her pantry, why she didn’t become ill when the other diners did, and why she disposed of a food dehydrator after the deaths and told investigators that she didn’t own one.