It was a trial that laid bare Erin Patterson’s life for the world to see, post by post, detail by intimate detail.

Here was a woman on trial for murder, who spoke about being weighed on scales by her mother as a child, scolded for becoming fat. Here was a family whose most intimate tensions in a private chat were exposed and beamed onto courtroom walls, message after message. Here was a courtroom that heard, over and over, of roadside stops filled with diarrhoea and of the need for doggy bags filled with soiled tissues.

Here was a jury that heard nearly every intricate detail leading up to the fatal mushroom lunch. Almost.

Patterson was eventually convicted of three counts of murder and one of attempted murder over the beef Wellington lunch on July 29, 2023, that killed her in-laws, Don and Gail Patterson, friend Heather Wilkinson and left local pastor Ian Wilkinson in a coma.

Here are the pieces of evidence the jury never heard:

Poisonous plants and homicidal toxins

Documents on poisons were found on Patterson’s electronic devices during a police search of her Leongatha home.

A pre-trial hearing was told she’d accessed a 2007 book titled Criminal Poisonings, from which police had discovered she’d saved a single appendix – “common homicidal poisons” – onto her Samsung tablet.

The deep dive of Patterson’s electronic footprint also uncovered a string of other findings, including an article about 50 cases of red kidney bean poisoning in the UK from 1976 to 1989, and a string of Google searches for words including “poison” and “hemlock”, a highly poisonous flowering plant.

Patterson’s devices had also accessed the iNaturalist website and a post made in September 2022 that pinpointed the location of a suspected sighting of hemlock at Loch in Gippsland.

On a third mobile phone seized by police they also found a paper the jury was never told about titled One step Purification and Characterisation of Abrin Toxin from Abrus Precatorius Seeds, about extracting toxic material from seeds.

A black Scorptec computer recovered from Patterson’s home revealed a 2011 Victorian Naturalist journal that referenced death cap mushrooms growing under oak trees. This was also excluded, but the judge’s reasons why were not aired in open court.

The poisoning of Simon Patterson

A key part of the police investigation was that the deaths of Don and Gail Patterson and Heather Wilkinson weren’t the first time the accused had dabbled with poisons.

At the same time as her murder charges over the trio’s deaths, and an attempted murder count for lunch survivor Ian Wilkinson, police had also slapped Erin Patterson with three counts of attempted murder.

The charges related to alleged attempts to kill Simon Patterson – the father of her two children – in 2021 and 2022.

They maintained that medical evidence showed Simon Patterson had become severely unwell after eating meals prepared by the accused killer, even ending up in intensive care and losing part of his bowel on one occasion.

The pre-trial hearing was told that Erin Patterson cooked Simon Patterson penne bolognese on September 19, 2021, before he was hospitalised in Leongatha with gastro-related symptoms.

She cooked him chicken curry during a trip to Howqua in May 2022, followed by a chicken curry wrap on a trip to Wilsons Promontory in September 2022. Both times, he ended up in hospital with severe bouts of illness, including one that placed him in a coma for 16 days before three parts of his bowel were removed during emergency surgery.

Prosecutors also told the court of a fourth meal, of beef and rice, in mid-2022 that Erin Patterson was never charged over. They claimed the meal prompted another trip to hospital for Simon.

The prosecution said they wanted the jury to hear this evidence because it helped prove their assertion that the deadly beef Wellington lunch was no accident.

Shortly before the trial, the prosecution revealed they’d also discovered an article on barium carbonate – also known as rat poison – which was accessed on one of Erin Patterson’s electronic devices about the time of her estranged husband’s third hospital admission.

They said a medical expert could provide evidence that Simon Patterson’s sudden onset of illness at that time was consistent with barium carbonate poisoning.

But the defence argued there was no rock-solid evidence that their client ever tried to kill her estranged husband, and there was no animosity between the pair at those times.

They said they feared that if the jury was allowed to hear about the allegations, there was a danger they would misuse the evidence and punish the accused woman unfairly.

Prosecutors had one final dip at getting the evidence before the jury, taking the matter to the Court of Appeal. But after also losing that fight, they decided on the eve of the trial to drop the three attempted murder charges relating to Simon Patterson, and he was restricted from talking about it during his evidence to the jury.

True crime fans and friendships

One piece of evidence the jury did hear was Erin Patterson’s connection to a true-crime fan page named “Keep Keli Lane Behind Bars”.

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Lane was a former Australian water polo player jailed in NSW for killing her newborn baby in the ’90s.

The group discussed absolutely everything, Patterson would tell the jury. Their children and families, recipes, world events, politics and true crime.

But the interest of page members spread much further than Lane, and the intricate details of what they talked about were kept from the jury.

Daniela Barkley joined when there were about 50 members; it eventually ballooned into a few thousand.

“We just discussed mainly the Keli Lane case and very often people post news articles or links to news about other cases that were coming up in the media. Anything true crime-related,” Barkley said.

The court heard Patterson was an involved member, undertaking crime-related research and was known to have a large collection of books on the subject.

But when the group began to implode due to personal conflicts, arguments and allegations of bullying, Barkley started a breakaway group with people she believed were “sane”, including Erin Patterson.

In this group, Erin Patterson would complain about her in-laws and issues she was having with her estranged husband.

But in the aftermath of the fatal lunch, the group was thrust in the midst of a real crime drama.

At a pre-trial hearing, group member Jenny Hay revealed she and others worked like amateur detectives to try and get to the bottom of what had happened.

Patterson deleted her Facebook page following the lunch and later reactivated it unexpectedly.

Her online associates noticed her profile, titled Erin Erin Erin, had disappeared and that she was using a new profile name during her return to the online space.

As the official police investigation drew on, rifts began to emerge between the online friends.

Christine Hunt told the court fellow group member Shelly Ridyard, who was later dropped from the witness list, allegedly began outing witnesses who’d spoken to police.

“I sent her a message that it was inappropriate to be commenting online, and it was against what we signed as witnesses. She made negative comments to me and blocked me,” Hunt said.

While three of the women later testified in the trial, the defence had tried to have their evidence spiked, removing Ridyard altogether, telling the judge that Patterson’s interest in the true crime genre was “irrelevant”, and the women had never met in person.

“A powerful sense of the gossip and rumours that was occurring on that forum both before these events and after these events, and the ways in which those people communicated to each other and told each other things about what was going on, which is extraordinary,” Mandy said.

Barkley admitted she listened to podcast episodes on the case the same day they came out and was penning a book on the mushroom case. She contacted a journalist she believed was also writing a book because she thought it would spark healthy competition.

“It’s all very infected evidence,” Mandy argued. A murky, gossipy underworld.

Mushroom trips

The Morwell jury was taken in detail through evidence gleaned from mobile phone cell towers about the movements of Erin Patterson’s phone in the months before the fatal lunch, to areas including Loch and Outtrim in Gippsland.

But there were other outings that prosecutors initially planned to tell the jury about. They included possible visits to the area on April 29, 2023 and May 5, 2023.

The timing was important because the police case was that Erin Patterson had made the trip to Loch and stayed there for approximately an hour.

“Then she goes to Leongatha and buys a dehydrator,” Crown prosecutor Jane Warren said.

The defence argued the ‘pings’ could be in line with Erin Patterson simply driving around her home town, because country cell towers are more spread apart than in metropolitan areas.

Prosecutors eventually abandoned attempts to get the trips into evidence because of a lack of granular data.

Household rubbish bins

Plenty of people forget to put the rubbish out on bin night. But prosecutors claimed Erin Patterson’s oversight was evidence that her later trip to a tip was nefarious.

The court heard Erin Patterson’s household bins had plenty of space for further rubbish. So her trip to Koonwarra transfer station to dispose of a black Sunbeam dehydrator was unnecessary – unless she never wanted it to be found.

“This wasn’t an ordinary lunch, this is a lunch at which the accused served a meal that contained poison,” prosecutor Sarah Lenthall argued.

“This wasn’t an innocent trip to the tip.”

Erin Patterson’s imaginary cat

Erin Patterson had many pets, including a dog and goats. But she didn’t have any cats.

Which is what made one post to her Facebook friends all the more peculiar.

“My cat chewed on this mushroom right now, he’s having a vomit,” Erin Patterson wrote, with a picture attached.

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The court heard an SD card found at her Leongatha home during a police search contained a string of mushroom photographs, both foraged and growing in the wild.

Also on the device was the picture of the cat she never owned.

The cat picture seemed strange but innocuous in pre-trial argument, coming up again at the pointy end of the trial and twice delaying the case as the prosecution and the defence argued about showing it to the jury.

Mandy made a last-ditch bid to bring the evidence, earlier ruled out by the judge, back in to support his client’s claims that she picked mushrooms.

But he only wanted to show the jury images of mushrooms, not of the cat. When he was permitted to do so, some of the photographs – less than a dozen – were shown to the jury.

In the end, the cat stayed in the bag by agreement.