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

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

Driving off the south Gippsland Highway in regional Victoria, the road carves a path through the vast green pastures, hidden under a layer of lifting fog.Different shades of green mingle in the landscape while animals graze on the short grass.