An alleged murderer testifying as a witness in their own defence is a rare strategy and normally a last resort.

The world has met Erin Patterson as the murderous cook behind a mushroom meal that killed three relatives. But years before her courtroom infamy, the woman from Melbourne's suburbs divided opinions.

Australian woman Erin Patterson has been found guilty of murdering three of her estranged husband’s relatives, who died after she deliberately served them poisonous mushrooms for lunch.