Erin Patterson's murder convictions for the deaths by mushroom poisoning of her estranged husband's relatives has prompted fevered speculation across Australia about her motive.

Erin Patterson, the Australian woman accused of killing three relatives with a meal of death cap mushrooms baked in a Beef Wellington lunch, has been found guilty of three counts of murder and the attempted murder of the lone survivor.

As the jury revealed its verdict, a tension built over weeks of legal arguments and disputed versions of what happened the day Erin Patterson hosted her in-laws for lunch was resolved.