Epefania Suluape, who killed her abusive and philandering husband with an axe, has had her 7 1/2-year jail term cut to five by the Court of Appeal.
Paulo Suluape, a noted Samoan tattooist, died under a flurry of blows from his wife as he played the electric organ in a sleepout at their South Auckland home in November 1999.
Mr Suluape had just told his 53-year-old wife he was leaving her for another woman.
In June last year, Suluape was convicted of manslaughter and sentenced to 7 1/2 years for what the trial judge said was a brutal killing.
At Suluape's appeal, Kevin Ryan, QC, said the sentence did not reflect the effect of a long process of abuse and degradation to which she was especially vulnerable because of her ethnic and cultural background and to which her offending was the ultimate response.
The Crown's contention, accepted by the sentencing judge, Justice Tony Randerson, was that it was a cold-blooded killing without significant mitigating elements.
Mr Ryan told the court that the relationship involved physical and emotional violence, including bashings, cutting with a machete, infecting her with venereal disease and continued infidelities.
In October 1999, Mr Suluape took his lover, a European woman, to a tattooist convention in Samoa, where his wife's family was prominent.
Justice Randerson said there was an element of deliberation about the attack.
He did not believe the assaults occurred with the frequency claimed by Suluape during the marriage.
Nor did he believe that Suluape was under any threat whatsoever from her husband at the time of the attack.
The judge was satisfied that she killed her husband in a fit of anger when he told her he was leaving her for the other woman.
It was a case, he said, that bordered on murder and the jury's manslaughter verdict could be seen as merciful.
He accepted, for sentencing purposes, that her husband's behaviour was provocative, and the incident in Samoa would have been a particular insult to any woman, particularly one of Samoan culture.
Mr Ryan told the Court of Appeal that the judge had focused too closely on the events of the night of the killing and not sufficiently on the response by a woman with an exemplary record who had been subjected to sustained and ultimately irresistible provocation.
Battered women's syndrome had been raised as a defence, but the Court of Appeal said this deflected attention from a much more pertinent consideration of the nature of chronic domestic abuse and humiliation.
In cutting the term, the court said that the sentencing judge had looked too narrowly at the events of the night. The couple's past history and its effects on the woman were highly relevant.
The court said it had difficulty with the judge's assessment of "callous conduct after the killing".
"There is nothing in her lifetime of service to her family in the face of spousal abuse and humiliation to suggest that callousness was any part of her character."