The eyes of the world were on a regional Victorian courtroom this week when a jury revealed their verdict to the world — that Erin Patterson had murdered three people with a deadly mushroom lunch.

The 50-year-old mother-of-two was on Monday found guilty of killing her estranged husband Simon’s parents Don and Gail Patterson, 70, and aunt Heather Wilkinson, 66.

She was also found guilty of the attempted murder of Wilkinson’s husband, Ian, 68.

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Patterson had served her guests beef Wellington parcels laced with death cap mushrooms during their visit to her home in Leongatha in July 2023.

Now, court authorities have revealed how a pool of 15,000 people was whittled down to the jury of 12 that ultimately decided her fate, and why the Latrobe Valley Law Courts in Morwell was chosen to host the 10-week trial.

Patterson was charged over the deadly lunch in late 2023.

But it wasn’t until April 2025 that the prosecution began putting its evidence before a jury and Patterson, who had pleaded not guilty, could defend herself.

Even before one of the country’s biggest court cases in recent history began, the wheels were already turning to pick a jury that would judge the facts and deliver a verdict.

It was February 2025 when 15,000 people from within the Latrobe Valley District in southeastern Victoria were sent letters notifying them they had been selected for jury service to cover several court matters starting in late April and early August.

That pool was trimmed by almost half after each person answered an online questionnaire judging suitability and availability, with 7000 excused, deferred, deemed ineligible or disqualified.

“All applications are individually assessed but factors that can be considered include illness, significant travel requirements, financial hardship, caregiving, proficiency in English, and being involved in the administration of justice,” a spokesperson for the Supreme Court of Victoria said.

Weeks later, in March, 1400 people from the remaining pool of 8000 were selected at random and sent a summons to attend court.

Given the attention and expected length of the trial, initially thought to run for about six weeks, a larger than normal number of summonses were issued “in case the jury needed to be discharged and a new jury empanelled”.

Of the 597 people that remained by mid-April, 234 confirmed they would be available for the trial.

Half of those were confirmed to attend on April 29, the Patterson trial start date, and the others were assigned to another jury pool.

“During empanelment, jury panel members were known by a number rather than their name, as is standard practice. Their occupation is also provided,” a Supreme Court spokesperson explained.

“Normally, the jury panel sits within the trial courtroom to receive information and directions from the judge and go through the selection progress.

“Because of the size of the panel, jury panel members were spread across the trial courtroom, another courtroom on the same level, and the jury panel room.

“The other two rooms were connected to the trial courtroom via video link so panel members could see and hear Justice Christopher Beale and the parties.”

Beale offered the panel an overview of the case and a list of 137 names featuring witnesses, places, and legal practitioners involved.

This allowed panel members the chance to be excused on the grounds they knew someone involved or felt they could not be impartial.

“Over the last 20 months, there have been many newspaper and magazine articles about this case, there’s been extensive radio and television coverage, there’s been online commentary and podcasts,” Beale told the panel.

“As potential jurors, you have to consider whether you can bring an impartial, open mind to the consideration of the evidence that will be led in this case and can decide the case solely on that evidence.

“If you can’t do that, or if you think you may struggle to do that, if you have doubts about your capacity to do that, you must ask to be excused.”

Twenty-seven people were excused, including 21 who knew someone on the witness list or with particular information about the trial.

Four people left due to medical reasons, and one each were dismissed because of travel and carer responsibilities.

Patterson’s jury challenge

The numbers of the 85 remaining panel members were put into a box and shaken before a judge’s associate picked one at random, announcing it and reading out that person’s job in the outside world.

“That person then walked into the trial courtroom, if they weren’t already there, and along a set path in front of the accused seated in the dock before taking a seat in the jury box,” a court spokesperson said.

“If the person sat down without the accused either saying ‘challenge’ or the prosecution saying ‘stand aside’, they became part of the jury.”

Three people were challenged by Patterson, the maximum amount the accused is allowed to make without providing reasons.

The prosecution did not stand aside anyone.

Only 12 jurors can deliberate on a verdict, but 15 were selected so the trial would not be derailed by illness or if someone needed to be excused.

Ten men and five women aged in their 20s to 70s were selected and asked to take an oath or affirmation to “faithfully and impartially try the issues” and “give a true verdict according to the evidence”.

It was then the trial of Erin Patterson could begin.

Juror #84

The judge informed the jury at the start of the trial how they should evaluate the evidence, and before deliberating told them of “the law and their task in more detail”.

“The jury were told they must not read media coverage of the trial nor conduct their own research into any topics raised during the trial,” a court spokesperson said.

One juror was discharged in May following concerns they may have discussed the case with family and friends, which went against instructions.

“I have not made a positive finding that juror number 84 discussed the case with family and friends but neither could I dismiss the possibility that he had. I was of the view that it was at least a reasonable possibility that he had breached my instructions,” Beale said.

Following the judge’s charge, and with 14 jurors remaining, two needed to be balloted off to get a final 12.

The process to do this was the same as during the empanelment, with two numbers randomly drawn out.

“I don’t know whether you’ll feel relieved or frustrated, but be assured you have made an important contribution to the administration of justice by your presence on this jury,” Beale said.

“I’m very grateful for it and I think the community would be very grateful too.”

While most juries are able to go home at the end of each day of deliberation, that was not the case this time.

Jurors were sequestered at a hotel, forced to surrender their phones and other digital devices, and could not watch free-to-air television or read the news.

It is a rare move, with the last jury sequestered in the Supreme Court being in December 2022.

It was revealed this week that jurors in the triple-murder trial had stayed at the same hotel as a key police witness and members of the prosecution during the majority of their deliberations.

Beale said there had been no interaction between them and the jury, with the jury on a separate floor and forced to eat meals in a conference room away from guests.

On Monday, after months of evidence and a week of deliberations, the jury foreperson confirmed they had reached a verdict, convicting Patterson of three murders and one attempted murder.

Juror pay

Jurors are paid $40 per day for the first six days and $80 every day after that.

“The juror’s employer is required to pay the difference between this amount and their usual wages,” a court spokesperson said.

Beale said the jurors had been “exceptional” during the lengthy process.

“The way you’ve conducted yourself throughout this trial has caught my attention and you’ve remained in good spirits even though the trial went much longer than you were led to believe and even though this was a major intrusion in all your lives, so I thank you again,” Beale said.

For their time, they were given a 15-year exemption from being called for jury duty again.

The venue for the trial was the Latrobe Valley Law Courts in Morwell, two hours east of Melbourne.

This venue was chosen in line with the Criminal Procedure Act, with the trial of an accused “to be held in the court sitting at the place that is nearest to the place where the offence is alleged to have been committed”.

There had been an application in July 2024 to move the trial to Melbourne, with claims the three murder charges should be regarded as having been committed in the Heidelberg hospital where Don, Gail and Heather had died.

“Whilst not disputing the (Public Prosecutions) Director’s entitlement to frame the offence date and location based on date and place of death, I do not regard this fact as leading to the interpretation that that is where the offence is alleged to have been committed,” Justice Jane Dixon said.

“In fact, as a matter of common sense, as argued by (Patterson’s defence barrister Colin) Mandy, the Crown will submit to the jury that by the time (Patterson) had administered the luncheon food to the three deceased, she had, on their case, committed the actus reus for murder.

“The offending will be alleged in the Crown’s opening statements to have been committed in Leongatha notwithstanding that the offence was allegedly completed by the death of the three alleged victims in Heidelberg.”

No other applications for a venue change were made.

Erin Patterson will be sentenced at a later date.