Erin Patterson is appealing her convictions for a fatal lunch involving poisonous mushrooms that killed three relatives, while prosecutors argue for a stricter sentence.

Triple murderer Erin Patterson has returned to court as her legal team pursues a formal challenge, arguing that jury accommodation compromised her trial.

Triple murderer Erin Patterson has launched a legal challenge against her convictions at Victoria's highest court, as defense lawyers cite jury contamination and evidentiary errors.