A winding valley ridge, a dead-end road. Where an unlikely murder weapon was found

Murder weapons can be found in the most unlikely places – such as a dog-leg stretch of dead-end road at the top of a winding valley ridge in the middle of nowhere in Gippsland farm country.

The strip of dirt and gravel is about 12 kilometres and four turns from the Bass Coast Highway heading out of Leongatha to Inverloch, cut along the top of a hill running to farms and homesteads that flow down the nearby slopes.

The area in Outtrim where death caps were found.Credit: Jason South

It was here that one of the country’s foremost mushroom experts, Dr Tom May, was out for a stroll on May 21, 2023, when he spotted a stand of death cap mushrooms.

Thick brush and eucalyptus trees covered the verge on the track, except for a smattering of oak trees – the life-support system for death caps to grow.

At least five mushrooms had sprouted amid a pile of fallen oak leaves along the side of the dirt road, and were thriving after days of rain had blanketed the ridge line. The distinct yellow colour, intricate gills and broad cap made it no doubt these were Amanita phalloides, one of the most deadly fungi found in the natural world.

Talk about a coincidence. May was in the area giving a community lecture on mushrooms when he had decided to go for a walk.

A screenshot of the post Tom May made to the iNaturalist website in May 2023.

May snapped some pictures of the Amanita phalloides and uploaded the images to the iNaturalist online forum, the clearing house for amateurs and experts tracking sightings of Australia’s flora and fauna.

Fatefully, it now seems, the world-renowned mycologist known online as “FunkeyTom” also GPS-tagged his find, dropping a pin that was accurate to less than 20 metres to what he found under a canopy of an oak tree.

Police suspect that within 24 hours, May’s post would be twisted into something nefarious by Erin Patterson, the introverted but highly intelligent small-town mother who would kill three people and seriously injure another after cooking them a meal of beef Wellington which contained a mushroom layer.

Mushroom expert Tom May outside court on May 14.Credit: Justin McManus

The King v Erin Trudi Patterson

It’s a crisp early morning in May this year. Too early for anyone to be out and about on the footy oval. Even the handful of visitors camping on the edge of the field are asleep inside their tents.

A ring of mature oak trees runs alongside the boundary line of the oval, plaques honouring Australia’s servicemen and women at the feet of the imposing trees.

Fallen leaves blanket the roots of the trees by a suspension bridge over Allsop Creek that links the reserve to the nearby hamlet of Loch.

Retired pharmacist Christine McKenzie outside court on May 19.Credit: Jason South

It is in this slice of country paradise surrounded by the rolling hills of South Gippsland that the prosecution believes Erin Patterson might have found her poison of choice – death cap mushrooms.

The prosecution case is that Patterson, armed with a knowledge of the deadly fungi, did what any foraging enthusiast would do – visit the iNaturalist website.

Just over a month before Tom May ventured out on that dead-end road in Outtrim, Christine McKenzie was walking a dog in the nature reserve in Loch, about 15 kilometres from Leongatha, when she noticed a stand of death caps growing under the canopy of an oak tree on April 18, 2023.

A former poisons information specialist at the Victorian Poisons Information Centre, McKenzie recognised the yellowish-green caps immediately. These were highly toxic death cap mushrooms.

Erin Patterson was found guilty on all three counts of murder and one of attempted murder.Credit: Marija Ercegovac

McKenzie, who was with her grandson at the time, took photos of the mushrooms, took the dog poo bags and plucked any mushroom she could see, concerned that someone might get seriously ill.

“I know that the Loch kindergarten sometimes have bush kinder where they take the kids to that sort of general area, so I was very keen to remove all of the samples that I could find of them,” McKenzie told Patterson’s Supreme Court trial.

But McKenzie decided to mark her discovery publicly as well, uploading a post of the find to iNaturalist with four photos and a GPS tag that pinned the location of the now-destroyed mushrooms down to a few metres.

This would be, the court heard, only the second known, publicly available, mention of death caps being found in the Gippsland area in two decades.

A mushroom found at Loch Reserve.Credit: Jason South

No death cap mushrooms were growing under the canopy of the oak trees when The Age visited the reserve that early morning in May, which was too early and warm in the season for the wild fungi to grow.

However, when The Age photographer Jason South returned in mid-June, he spotted a distinct yellow-green cap amid the brown fallen leaves pooling in the roots of a mature oak tree.

This masthead has not verified with an expert that the mushroom South found was a death cap, but the distinctive white gills and stem and coloured cap were all features consistent with the highly toxic variety.

The prosecution theory was that Patterson, who was by now suspected to be a regular user of the citizen science website, was keeping an active watch for sightings of her weapon of choice.

‘I was very keen to remove all of the samples that I could find of them.’

Chrstine McKenzie in her evidence about discovering death cap mushrooms in Loch

Ten days after McKenzie uploaded her post, the trial heard, mobile phone records “suggest” Patterson travelled from Leongatha to the vicinity of the Loch Reserve.

Two hours after that, she arrived at the Hartley Wells Betta Home Living shop in Leongatha, where she paid $229 for a Sunbeam Food Lab electronic dehydrator with her credit card.

The iNaturalist site would again point the way when Patterson reached the final stages of enacting her plan, when Tom May posted about his death cap encounter.

‘Speculation upon speculation upon speculation’

To Patterson’s defence barrister, Colin Mandy, SC, this was a house of cards.

The mobile phone pings were so generic they couldn’t put Patterson in the general area of Loch and Outtrim in South Gippsland, let alone at the specific locations of the death caps GPS-tagged in the iNaturalist posts. And mobile phone towers in the area are spaced much further apart than in metropolitan Melbourne.

The 30-kilometre stretch of road that links Leongatha with Loch meanders through rolling hills and paddocks dotted with cattle and the occasional homestead.

There’s little by way of major towns other than Korumburra, a pit-stop almost exactly halfway between Leongatha and Loch on the tree-lined South Gippsland Highway.

Erin Patterson’s defence barrister, Colin Mandy, SC.Credit: Eddie Jim

The route to Outtrim is perhaps even less populated, zigzagging through steep hills and farms perched on rolling slopes, with little signs of life other than an occasional car and grazing herd.

‘And our position to you: are we in a world of total speculation? Is that really the argument? Speculation upon speculation upon speculation.’

Defence barrister Colin Mandy, SC, addressing the jury

The bucolic drive ends abruptly after about 20 minutes when the Short Street turn-off creeps up on Outtrim-Moyarra Road, climbing up a hillside to tree-lined Neilson Street.

Mandy argued there was “not one scrap of evidence” that Patterson had ever returned to the iNaturalist website after that single visit in May 2022 or that she saw the posts made by Tom May and Christine McKenzie.

“And our position to you: are we in a world of total speculation? Is that really the argument? Speculation upon speculation upon speculation,” Mandy told the jury in his closing argument.

Patterson’s denials in her evidence were emphatic on these points.

Did you ever forage for mushrooms in Loch, in Outtrim? Did you see the posts by McKenzie or May?

“No, no, no, no,” were her answers.

“My only interest ever was to find out if they lived in South Gippsland or not,” Patterson told the jury.

The jury clearly felt differently.

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