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

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.

While Patterson has been found guilty of cooking the deadly mushroom lunch that killed three of her relatives and left another seriously ill, the motive is still unclear. There may simply be none. "You might be wondering, 'What is the motive?'" said prosecutor Nanette Rogers SC when she spoke to the jury in the trial back in April.