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

The jury was sequestered in the same hotel as a key police witness in Erin Patterson's murder trial and two members of the prosecution's team were staying.

An Australian woman was on Monday convicted of murdering three elderly relatives of her estranged husband with a meal laced with poisonous mushrooms, and attempting to murder a fourth, in a case that gripped the country.