The domestic violence murders of two Sydney teenagers were preventable, says a coroner who found a litany of errors made by multiple authorities.
Jack Edwards, 15, and his sister Jennifer, aged 13, were shot dead on July 5, 2018, after their father John Edwards stalked his daughter on her way home from school.
NSW State Coroner Teresa O'Sullivan on Wednesday found police failed to make reasonable inquiries after the children's mother, Olga, reported instances of Edwards' abuse and stalking in 2016 and 2017.
Gun registry staff, in the job without any formal training, then failed to recognise Edwards' long pattern of domestic violence when granting him various permits and licence to shoot and buy pistols and rifles.
The coroner could not be satisfied Edwards initially started gathering permits in order to murder his children.
But she said he'd formed that intent by April 2018, when he acquired his second pistol.
Her voice wavering at times, the coroner said it was unquestionable the deaths of the children and their mother's December 2018 suicide had caused unbearable suffering for many.
"However, to describe this as a tragedy is to import a sense of inevitability that nothing could have been done to change the outcome," she said.
"Instead, the evidence before this court plainly reveals the deaths of Jack and Jennifer were preventable."
Among her 24 recommendations, Ms O'Sullivan has called for the process allowing people to shoot guns on-the-spot to be abolished, police officers' training to include more on domestic violence and regular audits of police reports to ensure they comply with best practice.
Despite the NSW Police's overhaul of the gun registry in response to the deaths, the coroner said more was needed to address the "serious, systemic failures" present until July 2018.
She also called for better information sharing between the police and the registry to verify answers given by applicants, including whether they were subject to family law proceedings.
Independent children's lawyer Debbie Morton, who was tasked to represent Jack and Jennifer's best interests in the Family Court, was referred to a NSW lawyers' body for possible disciplinary action.
The coroner found she hadn't properly considered objective evidence, statements by Olga Edwards and the children's concerns before addressing the Family Court on Edwards' risk.
Gun clubs that interacted with Edwards in 2016 and 2017 adhered to their obligations, the coroner found.
But she recommended a new law forcing gun clubs to tell the registry when they refuse someone membership and give reasons.
Unlike other inquiries, the coroner cannot extend her inquiry and recommendations to address community-wide issues if they don't relate to the deaths in question.
"Notwithstanding, the deaths of Jack and Jennifer serve as a stark remainder of the broader systemic problems that face too many women and children every day," the coroner said.