Grieving father makes a desperate plea for answers as he campaigns for a public inquest after his psychopath father-in-law murdered his entire family
- Peter Miles shot dead his wife, his daughter and her four grandchildren in 2018
- Children's father Aaron Cockman alleged Miles family had history of violence
- Mr Cockman is still searching for answers and pleading for a public inquest
A grieving father whose family was murdered in one of Australia's worst massacres is still desperately searching for answers into what happened.
Peter Miles, 61, shot dead his grandchildren, Taye, 13, Rylan, 12, Ayre, 10 and eight-year-old Kayden, their mother Katrina and his wife Cynda, before turning the gun on himself at the family's farm in Osmington, Western Australia on May 11, 2018.
The children's father and Katrina's ex-husband Aaron Cockman has alleged Miles' family had a history of violence prior to the mass killing which had drawn the attention of authorities.
He is fighting for a public inquest as he believes the the Family Court of Western Australia played a role in fuelling the family conflict in the lead-up to the mass killing.

The bereaved father (pictured) is calling for a public inquest into his children's deaths to prevent similar family tragedies

Peter Miles (second from left in suit and blue tie) killed his wife, Cynda, (back right), his daughter Katrina Miles (left in red dress) and her four children aged from eight to 13 (pictured left to right Rylan, Kayden, Taye and Ayre) before shooting himself
In his letter to the WA Attorney General, Mr Cockman asked why the state and its Coroner would not want to investigate what happened.
'I am writing to you personally to ask you to insist that the WA Coroner carry out a full and transparent inquest into the seven deaths of members of my family,' Mr Cockman wrote.
'I do not believe I should have been put in the position of having to request this - I think this is something that the whole community expected, given the extreme and public nature of the tragedy, and I think that everyone should want to find out any possible ways of preventing a repeat of such an event, rather than carrying out a secret inquest that doesn’t investigate some of the most obvious and important aspects of this case.
'Why would there not be one into such an extreme set of murders when there is a clear opportunity that it might illuminate ways to protect future generations of our children?'
The murder of Mr Cockman's family shocked the nation.
It was the worst mass shooting Australia has seen since the 1996 Port Arthur massacre in Tasmania which led to mass gun reform.
At the time of the murder-suicide Mr Cockman had been locked in a bitter custody battle over his four children.

Miles (centre) is pictured with his four grandchildren, his daughter Katrina (bottom-right)and wife Cynda

Aaron Cockman (pictured in August 2018) has alleged the Miles family had a history of violence - which included the killer grandfather's son taking his own life
He said Miles had paid about $100,000 in legal fees for his daughter and the litigation had heightened tensions within the family and caused them to 'spiral out of control'.
The bereaved father claimed Katrina meanwhile - who he broke up with in mid-2014 - had threatened to kill both herself and the children they shared by crashing into a tree.
Mr Cockman has alleged the Miles' family had a history of violence prior to the mass killing.
Mr Cockman said Miles' son took his own life and had previously burned down a shed during a family dispute, according to The Australian.

The grisly murder-suicide at a remote farm house (pictured) in Western Australia shocked the nation. It was the worst mass shooting since the Port Arthur massacre in 1996
It is also alleged Miles's own father had tried to kill him.
A month before his family's massacre, Mr Cockman was on Facebook accused of stalking and harassing by Katrina but the court allowed supervised visits and he was given favourable reports.
A week before May 11, Mr Cockman went to the cinemas to watch the new Avengers movie with his children and estranged wife.
Katrina home-schooled her four children at the farm after they moved there when her marriage broke up.
Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14.