If this all adequately recounts the events, then the public has a right to ask about the defence of provocation, or circumstances where any reasonable person might be capable of losing the power of self-control.
But a fair old outcry after absurd self-defence claims in the trial of Clayton Weatherston for the murder of his ex-girlfriend in Dunedin in 2008 seems to have led to toning-down of the provocation defence to the point where it is now more a mitigating factor in sentencing, rather than a pathway to acquittal.
When such an approach also rules out leniency for a battered woman who has finally exterminated the partner, the public can perhaps take a good look at itself, and ask whether it gave the politicians a little too much scope.
The Weatherston case was never a case for changing any rules, other than how trials are conducted.
Perhaps now many more can ask themselves in what circumstances they, too, might be incapable of maintaining the power of self-control.