Mr Veale said the fact their father had given bullet cartridges to the children as a present months before the incident, as well as the fact Livingstone's estranged wife, Katharine Webb, had reported he had raped her, highlighted flaws in the system.
"We all make mistakes, but those were two salient types of behaviour that should have signalled a review of what the [Family Violence Interagency Response System] was looking at."
It was unacceptable the bullet cartridge incident was not known about by the whole group.
"The information sharing protocol should facilitate information from all parties - not just police."
Mr Veale lamented the fact diversion had been granted for "minor family offences" committed by Livingstone, even though they breached a protection order preventing him from contacting Ms Webb.
"This is not a question of warnings; the question is, 'How many days are you going to do in prison?'
"Government quadrupled the maximum penalty for these offences [from six months to two years], yet people are still dealing with this and calling them 'minor'."
University of Otago law faculty dean Prof Mark Henaghan echoed Mr Veale's comments.
"Sadly, this [report] reflects something we've seen before. We are still are not taking the signs of violence in the home seriously enough. Why do we just let things roll on, hoping everything will be all right?"
The recommendation for increasing transparency between parties was "bang on", Prof Henaghan said.
"We should be doing a lot better. Each incident is looked at in isolation. There is no co-operation.
"If they all sat in a room and talked about what they really knew, we would be doing a lot better.
"Violence is a complex problem and a rife problem, sadly, in our society."
A specialist adult sexual assault (ASA) squad established in Dunedin in 2013 should be rolled out nationwide, as the report recommended.
"That's an easy one. Everyone needs to know about violence and the triggers of violence.
"Intervention in the early stages can help save lives."
