Nearly three years ago, police officers Matthew Arnold and Rachel McCrow were killed in cold blood by a trio of conspiracy theorists at a remote property in rural Queensland.
The trio, Stacey, Nathaniel and Gareth Train, went on to kill again that day, shooting an unarmed neighbour, Alan Dare. They shot and wounded a third police officer, Randall Kirk, and hunted a fourth, Keely Brough, as she hid during and after the shootings.
Many questions have remained unanswered, but inquest findings to be delivered on Friday are expected to address this.
What is already known is that the Trains set a deliberate ambush for Queensland police officers at their rural property near Wieambilla, about 270km north-west of Brisbane with prepared, camouflaged positions.
They were ultimately gunned down in a late-night shootout with police.
It was 12 December 2022. Police later described it as Australia’s first fundamentalist Christian terrorist attack.
But the Trains’ motive remains disputed and will be one of several questions state coroner Terry Ryan has been seeking to resolve.
He may also decide whether any change to police procedure or policy could reduce the likelihood of deaths occurring in the future.
Ryan has had more than a year to consider the evidence, with hearings wrapping up last August.
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He has heard evidence that the three Trains responsible for the killings had developed a rare disorder known as “folie à trois” or “shared paranoid delusions”.
Stacey Train and her ex-husband, Nathaniel, had been school principals in Queensland and New South Wales. They were well paid and experienced educators.
By contrast, his brother, Gareth – who was her new husband– was a deeply unimpressive person, a “keyboard warrior” and lifelong subscriber to various conspiracy theories.
But it was Gareth who was the leader, the inquest heard.
Forensic psychiatrist Andrew Aboud testified that Stacey and Nathaniel had effectively become afflicted by a delusional personality disorder identical to Gareth’s.
The inquest heard evidence that, during the Covid-19 pandemic, Gareth’s paranoia developed into delusional mental illness. He adopted beliefs that police were devils and demons, and needed to be fought to bring about the second coming of Jesus Christ, among others.
Ultimately the three died by “suicide by cop”, Aboud said. They had no broader message or cause than that created by delusions and mental illness, he told the inquest.
But not everyone accepted that their actions were solely understandable as the product of mental illness.
Josh Roose of Deakin University argued that their actions were a form of terrorism, violence intended to further a political goal, their ideas created through “algorithmic radicalisation”.
Roose said their online algorithm had shown them increasingly extreme, more exciting material until they formulated a plan to kill.
At least part of that radicalisation process took place in YouTube comments. The Trains maintained contact with an American conspiracy theorist, known as Geronimo’s Bones, until the night they died.
The Arizona-based man, Donald Day Jr, has recently pleaded guilty to a firearms offence in Arizona.
The Queensland police also subscribe to Rouse’s view that the Trains were terrorists, according to evidence given by deputy commissioner Cheryl Scanlon.
Ryan has been tasked with considering nine primary questions regarding the tragedy, including the profiles and motivations of the three killers, and whether anything was known to the authorities that would have indicated a risk that they would kill.
Ryan has also been considering the actions of the state’s special emergency response team, which killed the three Trains in a shootout.
He is expected to hand down his findings from about 12.30am (AEDT) Friday.
