Though the unusual manner in which Aaron Cockman spoke of the alleged murderer of his children and ex-wife – his former father-in-law – was puzzling to many, psychological studies of similar crimes suggest a way to make sense of its seeming contradictions. By Martin McKenzie-Murray.

Margaret River and paternal familicide

This doesn’t ordinarily happen, but here was Aaron Cockman, father of the four murdered children and ex-husband of a fifth victim, facing a media scrum. He spoke without notes, and took questions. Police had counselled against it, but they couldn’t stop him. He was free to speak. It surprised just about everyone. “Peter is an awesome man,” Cockman said of his former father-in-law and presumed mass murderer, Peter Miles. “Before all this blew up I’d get on so well with him. We’d go to the high-school farm and cut up sheep together. Enjoy the kids together. He was like my best friend and I still love who he was, but his mental attitude… If you get on the wrong side of someone...there’s just some people you don’t get on the wrong side of and this happened with Peter and Cynda. The kids were beautiful kids. Kayden was still at the age where he’d come up and give me a hug after I was cut off from the kids.”

In a case like this – a wicked and high-profile crime – police offer victims welfare support and their services as media liaison. They may help draft public statements and shepherd the grieving from the intrusive impulses of the media, including warning media outlets from staking out their homes or performing “death knocks”. If an investigation is live, victims may also be coached on their public statements, lest they reveal something damaging to the operation.

It is rare for someone who has just experienced the murder of a loved one to front the media. Rosie Batty was an exception, and predictably her statements after the murder of her son were followed by public scorn and the supercilious policing of her grief. “What triggered this was a case of his dad having mental health issues,” she tearfully told reporters at the front of her home. “He was in a homelessness situation for many years, his life was failing, everything was becoming worse in his life and Luke was the only bright light in his life. No one loved Luke more than his father. No one loved Luke more than me – we both loved him.”

Cockman’s press conference was a different affair. “It’s not some random guy off the street that’s taken them away from me,” he said. “He gave them to me. If it had to happen there is no better person than that. I wouldn’t want some random guy off the street doing what happened. The reason I’m standing up here is so that people everywhere, not just those who knew Katrina and myself, Peter and Cynda, don’t feel hatred.

“Peter didn’t snap. He’s thought this through. I think he’s been thinking this through for a long time. All the kids died peacefully in their beds. I had one question this morning. Was Kayden with Kat or in his own bed, because he’s still at the age that he sleeps with Kat. And I was told, yes he was in Kat’s bed. All the kids... the guy who went through and saw all the kids said they looked all peaceful. How the hell Peter did that, I still can’t figure out. He did a good job, did a really good job... They were all just very, very peaceful and calm. When I heard that, the best feeling came over me.”

For some commentators, Cockman’s praise of the alleged killer was bizarre or improper. Some seemed to suggest that we interpret his strange, grief-licked conference as proof of a cultural desperation to exonerate male killers. They reject what is characterised as the “good bloke” narrative. There were also those who questioned the media’s presentation of such reflections, though Cockman’s statement was unquestionably newsworthy, even if we might question the indulgence of a man so clearly stricken.


We shouldn’t simplify the horror of Osmington, near Margaret River, to one preferred, constituent part – and especially so when the facts aren’t in. We shouldn’t ignore context and psychology. We shouldn’t dismiss any behaviour of a killer that’s inconsistent with popular notions of villainy. To do so is to ask us to pretend that a man might only behave in a manner consistent with his crime – and to ignore that within many individuals there sounds a grotesque dissonance.

None of which is to say that masculinity does not bear upon violence, and certainly there have been entreaties this week to view these crimes through a lens of gender. In understanding the profile of these sorts of crimes, their peculiar pathology, gender is a useful marker.

Not only are men more violent than women, but they commit different types of violence. This is also true of filicide and familicide. In 1990, psychology introduced the notion of paternal filicide and in doing so recognised the importance of gender in these kinds of murders. Writing in a 2016 case study on paternal filicide-suicide for The Journal of Psychology, three psychologists noted: “Empirical evidence concerning paternal filicide suggests that, contrary to maternal filicide, the victims of fathers are often older children. Also, paternal filicide offenders appear to be much more likely than their maternal counterparts to commit or attempt to commit suicide afterwards ... Unlike mothers, fathers seem more likely to kill more than one child and pull along their spouses in the killing. Regarding the motive, fathers are also more likely to commit filicide as a means or a reprisal against their spouse while going through conjugal separation.”

Yes, the grotesqueness of this type of vengeance murder – think Robert Farquharson – is particular, if not unique, to men. In their 1988 book Homicide, evolutionary psychologists Martin Daly and Margo Wilson wrote about the male psyche as being “obsessed with social comparison, with the need for achievement and with the desire to gain control over the reproductive capacities of women”. They described familicide as a “peculiarly male crime” that “must be understood in terms of men’s proprietary attitude toward women and their reproductive capacity”.

The role of gender and masculinity is evident, too, in studies of violence against women following disasters. In the years following Victoria’s Black Saturday, police and family violence services detected an increase in violence, although data was inconclusive. Certainly, the data does uphold the thesis internationally – it was true in the aftermath of hurricane Katrina in the United States, and true following the Christchurch earthquake of 2010. In addition to the obvious stressors – financial, psychological – there often exists a compounding sense of injured masculine pride. For some men, disaster has unsettled their self-image of the strong, providing patriarch. In response to this came the inaugural conference into family violence and natural disaster, held in Victoria in 2012. The conference launched a PhD thesis by Dr Debra Parkinson, titled “The way he tells it…: Relationships after Black Saturday”. Speaking at the conference opening, Parkinson said: “We accept easily that violence against women increased after earthquakes in Haiti and cyclones in Bangladesh, but nobody wants to hear that men who embody the spirit of resilient and heroic Australia are violent towards their families. The theme of this presentation is the silencing of women.”   

To state the obvious: forms of ruinous masculinity – or masculinity applied ruinously – exist in dismal abundance. When examining violence, masculinity matters. And yet, if we are to somehow ban “good bloke” testimonies, we will be ignoring their significance, namely that they describe one particular clinical profile of the paternal offender, long established in the psychological literature: the morbidly altruistic killer.


Darren Milne was quietly, carefully preparing his family’s annihilation. Pregnant wife, two sons and himself. He paid off his debts and took leave from his job as an electrical engineer so he could rehearse the murder. His plot was diabolical: to careen the family car into a tree. If the collision didn’t prove fatal, he had rigged canisters of petrol designed to ignite after impact. Milne selected a tree besides a freeway, and made “practice runs”. He filmed all of this. “Learn the road backwards,” he wrote in a series of instructions to himself.

The Milne family was financially secure, and there was no recorded history of abuse. But Milne’s children – Liam and Ben – suffered from fragile X syndrome, a genetic disease causing intellectual disability, and which was causing Milne morbid anxiety. Milne had also been treated for depression, but close friends described him as a loving father.

On February 1, 2015, Milne enacted his plan. He and his wife, Susana, died instantly. His son Liam died at the scene. Ben survived.     

“It’s not worth it, neither of us have the skills to make it work,” Milne wrote to himself in a note discovered by police. “We have both given it our best shot over a long period of time. There is too much conspiring against us. G got the calculation wrong, it’s that simple. L and B are both happy. B doesn’t know it yet, it is a good time to go. It is only going to get tougher as time goes on. We have been totally S’d over, maybe we can stop it from happening to someone else. They are going to have to manage ADD and diabetes, it is going to be too much ... From this point on I need to be totally focused, forget everything else, need to source comfort from the fact.”   

As alarmingly counterintuitive as this may be, altruism – albeit of a grotesquely perverted kind – is a recurring motive in filicide and familicide. The killer, often depressed and poorly equipped to handle stress, comes to rationalise murder as a solution to his family’s trouble. “The majority (70%) of the motives for filicide-suicide were identified as altruistic, that is, the parents were motivated by the desire to alleviate real or imagined suffering in their children,” one psychological paper found, published in The Journal of the American Academy of Psychiatry and the Law in 2005. “The altruistic category was sub-divided into psychotic and non-psychotic.” 

The paper goes on to note of familicide that “perpetrators have been classified as accusatory killers or despondent killers. Accusatory killers had a grievance against their wives and often a history of violence. The despondent killer is described as ‘a depressed and brooding man, who may apprehend impending disaster for himself and his family’, and who sees familicide followed by suicide as ‘the only way out’.”

My suspicion is that when “good bloke” testimonies emerge in media reporting, they are being used to describe the despondent killer.

There is at the heart of the non-psychotic crimes, an awful egotistical delusion. Of Darren Milne, the coroner said: “It is unusual for a Coroner to comment on the conduct of a person who has taken his own life. Two other lives were taken by him and [his] actions should attract more than the usual disapproval attached to murder and suicide. He made assumptions about the quality of the boys’ lives. He disregarded the boys’ fundamental human rights. He disregarded potential advances in medical science potentially beneficial to the boys. He assumed successful execution of his plan without regard to the possibility that the front seat occupants, he and Susana, may not survive, but that one or both the rear seat passengers would survive, terribly injured, severely disabled or otherwise, or, worse, be conscious, trapped inside the cabin when the car caught fire.”

Geoff Hunt, another despondent killer, who murdered his family and himself on a farm in New South Wales, was described by the coroner as having an egotistical delusion. Like Milne, he had fashioned a horrifically corrupted and self-centred sense of virtue. Masculinity plays a part here. “Because of his emotional dependence on his wife and essential self-image of his position as head of a family that he believed was dependent upon him, his distorted logic led him to conclude that the children and his wife would not cope without him,” the coroner wrote. “He then set about systemically and cold-bloodedly killing each of them, before killing himself ... What Geoffrey Hunt did was inexcusable; the absolute worst of crimes. It was the result of an egocentric delusion that his wife and children would be better off dying than living without him.”

The coroner was also interested in the contradictions that dwelt within. “Generally, family and friends thought Kim and Geoff Hunt were both leading largely happy, stable, and successful lives, overcoming or at least coping with the adversity dealt to them. The manner of the deaths demonstrates the truth was far different. This inquest has sought to describe that dissonance.”

Whether we like it or not, that dissonance is precisely the thing distressed friends and family who recall killers fondly are suggesting. To try to censor the so-called “good bloke” testimonies is to cleanse the public record of voices – including victims’ – that don’t conform to this prescribed idea of villainy. We would demand of those who knew a killer to renounce all contradictory memories of them. We would tolerate no shocked qualifications, no admissions of surprise, however sincere. We would censor the raw and humanly fallible testimonies of the heart-stricken, because we’ve ruled them offensively complicating. We would ask journalists to turn off their dictaphones, and demand clinicians cease their misguided pursuit of understanding.

That dissonance is the sound of these crimes, the noise from which the West Australian corner will now try to make sense.


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This article was first published in the print edition of The Saturday Paper on May 19, 2018 as "Murderous intent".

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