The Sydney financial planner who shot dead his two children as they cowered under a bedroom desk was awarded gun licences despite "a propensity for domestic violence", stalking allegations and a gun club refusing him membership, an inquest has been told.
The NSW Coroners Court on Monday heard John Edwards was awarded licences to shoot rifles and pistols in June 2017 after NSW Firearms Registry staff used a police database report that had failed to pick up several matters related to domestic violence.
Over the next year, he legally acquired five weapons including the Glock 17A 9mm semi-automatic pistol he used to shoot dead Jennifer Edwards, 13, and Jack, 15, in the boy's bedroom in July 2018.
Edwards hired a car and stalked his daughter on her way home from school in order to learn their new address before he followed or chased his daughter inside.
Neighbour Bruce Wilson heard five shots over about a minute and approached the home, knowing "someone is shooting the children".
He eye-balled Edwards as the 68-year-old "half skipped" down the home's front stairs.
"I said 'Is everything OK, what have you done?'" Mr Wilson told the inquest.
"He didn't say anything, he just walked towards me.
"He was in no hurry, he didn't rush at all. Everything was methodical and well-thought-out."
The children were later found "crumpled together" under Jack's bedroom desk with multiple gunshot wounds, counsel assisting the coroner Kate Richardson SC said in her opening address.
Edwards killed himself at his home the night of the murders.
The "unimaginable tragedy" had affected many including family, friends and staff at the NSW Firearms Registry, which granted Edwards numerous permits in 2017 and 2018, Ms Richardson said.
"But most of all they devastated their mother Olga Edwards, who sadly took her life six months later."
The police investigation had uncovered Edwards had "a propensity for domestic violence" including physical and psychological assaults against the women of his life and his many children, Ms Richardson said.
One ex-partner said he was never physically violent but "controlling" while another said he was "unbalanced and a narcissist", the lead investigator told the inquest.
Including the two he murdered, Edwards had 10 children to seven partners.
The police database report generated in June 2017 included stalking allegations by three former partners and a provisional apprehended violence order issued to protect one of his adult children.
But due to the way the algorithm was written, it missed four matters in the police database related to Edwards, Ms Richardson said.
Three had been recorded "domestic violence - no offence" including an ex-partner's allegation that Edwards had threatened to come to her home, harm her and take her young child; and Olga Edwards' December 2016 report of three separate violent incidents by Edwards in 2015 against Jack and Jennifer.
The fourth report - of Olga being stalked at her yoga studio class after becoming Edwards' seventh ex-partner - was misrecorded by Hornsby police.
That error meant it failed to even appear on Edwards' police database profile, let alone the June 2017 report.
The inquest also heard the registry didn't know Ku-Ring-Gai Pistol Club refused Edwards membership in early 2017.
Club officials formed the impression the "aggressive" Edwards "was trying to railroad them", Ms Richardson said.
He then lied in correspondence with registry staff about why he needed to change clubs.
Coroner Teresa O'Sullivan is expected to review NSW's gun licensing process and whether more disclosure between gun clubs, the registry and applicants' ex-partners should be mandated.
Adam Casselden, acting for the NSW Police Force at the inquest, said the registry had made a number of changes since July 2018 to ensure the "tragic circumstances are not repeated".
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