Jurors deciding mushroom cook Erin Patterson’s fate will start their first full day of deliberations on whether she is guilty of triple murder.

The jury retired to consider its verdict on Monday afternoon as the Victorian Supreme Court trial reached its 10th week.

It will be up to the 12 jurors to decide whether Patterson, 50, intentionally served her lunch guests beef Wellingtons laced with death cap mushrooms.

Her former in-laws Don and Gail Patterson, and Gail’s sister Heather, all died after consuming the lunch at Patterson’s regional Victorian home on July 29, 2023.

Heather’s husband Ian Wilkinson also ate the meal but survived after spending months in hospital.

Patterson claims it was all an accident and has pleaded not guilty to three counts of murder and one charge of attempted murder.

The jury heard from more than 50 prosecution witnesses throughout the trial before Patterson entered the witness box for eight days.

The prosecution and defence then spent a week delivering their closing arguments, before Justice Christopher Beale provided his directions to the jury.

He said the jurors needed to consider whether the prosecution had proved beyond reasonable doubt Patterson deliberately served death caps with the intention to kill her guests.

Justice Beale reminded the jurors if they held any doubts about Patterson’s guilt, they must acquit her.

“You cannot be satisfied that the accused is guilty of an offence if you have a reasonable doubt if she is guilty of the offence,” he told the jury on Monday.

The jury is being sequestered during the deliberations and will have to remain together until unanimous verdicts are reached on all charges.

Justice Beale reiterated that every juror must agree on the verdict, although it did not matter how each person reached their conclusion.

The jury can deliver its verdicts any time from 10.30am to 4.15pm on Monday through to Saturday.

The jurors will still be sequestered on Sunday if they have not reached a verdict, but they will not have to deliberate.

Justice Beale reminded the jurors they cannot return home until their unanimous decision.