Erin Patterson is appealing convictions for murder of three relatives after a hotel confusion let the jury share accommodation with prosecution and a key witness, an error the defence says undermines the verdict.

Sarah Edney, Patterson’s barrister, calls the situation catastrophic and demands the convictions be quashed so that justice is both done and seen to be done.

The appeal also contests that phone‑tower evidence claiming Patterson hunted death cap mushrooms at two sites, as reported on a citizen‑science website, was speculative and unfairly prejudicial.

Defence lawyers argue that Facebook messages exchanged months before the lunch, which criticised Patterson’s estranged husband, were irrelevant and should have been excluded from the trial.

Victoria’s Director of Public Prosecutions is set to appeal that the 33‑year parole period is “manifestly inadequate” and that the sentence should be altered.

The appellate judges will take time to render a decision, meaning further developments could take weeks.