Chapter 8
The conceptual framework for reduced culpability

Setting the scene: Two illustrative cases

8.5To illustrate how charging and sentencing decisions may enable recognition of reduced culpability for homicide, it is useful to consider two New Zealand cases – those of Tikiahi Erstich and Jacqueline Wihongi.672

8.6Erstich and Wihongi are not the only cases we could have selected to contrast the different means by which the law may recognise reduced culpability for homicide, but they stand out. Having committed homicide when he was just 14 years old, Tikiahi Erstich is the youngest defendant in our case review. Ms Wihongi’s case, as noted in Chapter 3 and discussed in the following chapters, is significant in large part because the Court of Appeal considered the circumstances in which the presumption of life imprisonment for murder may be displaced for offenders who kill after severe and prolonged abuse.

Tikiahi Erstich

8.7We noted the case of 14 year old Tikiahi Erstich in Chapter 2.673 In 2001, after he had been subjected by his father to a 10-year “reign of terror” that included beatings with pipes and sticks, having his head battered against hard surfaces and being thrown against walls, Tikiahi Erstich shot and killed his tormentor at point-blank range. He was charged with murder and, at trial, relied on the partial defence of provocation,674 which the jury apparently accepted because it returned a verdict of manslaughter. He was ultimately sentenced to a two-year suspended term of imprisonment, imposed by the Court of Appeal following a Crown appeal against sentence.675

Jacqueline WihongiTop

8.8We summarised the facts and disposition of R v Wihongi in Chapter 3,676 and so we reiterate only immediately salient points here.

8.9In 2009, Jacqueline Wihongi fatally stabbed her partner. She was in her early 30s and had suffered years of sexual and physical violence, including gang rape, at the hands of the deceased and others. She was charged with murder and pleaded not guilty. She did not rely on self-defence or the partial defence of provocation, and the jury convicted her of murder. She was ultimately sentenced by the Court of Appeal to a 12-year term of imprisonment. She was spared life imprisonment because the Court of Appeal found that sentence would be manifestly unjust in the circumstances.


8.10These cases share two important features. The first is that it is probable both defendants were found to have killed with murderous intent.677 The second is that, in both cases, it was recognised that the defendants’ culpability was, in differing ways, reduced because of the violence they had suffered before the killings.
8.11The outcomes in these cases demonstrate how partial defences and sentencing can reflect reduced culpability for homicide. In Erstich, the partial defence of provocation likely meant the defendant was convicted of manslaughter, rather than murder, and sentenced on that basis, while Ms Wihongi, who did not rely on a partial defence, was convicted of murder. Despite this difference, both offenders received sentences that took account of their personal circumstances. Tikiahi Erstich’s sentence reflected the violence he had suffered, his youth and rehabilitative prospects and his low risk of future offending.678 Ms Wihongi was sentenced as a murderer but also in recognition of her personal circumstances. In combination with her cognitive deficits, Ms Wihongi’s history of abuse justified displacement of the presumption of life imprisonment,679 although her level of risk together with the need to deter and denounce the taking of a life were found to require a 12-year finite term.680
8.12New Zealand law no longer includes the partial defence of provocation or any other relevant partial defence,681 and so if Tikiahi Erstich was tried today, he could not defend the murder charge on that basis. A key question in this part is whether there is a need for a partial defence for cases of this kind or whether reduced culpability can – and should – be recognised principally through sentencing, as it was in Ms Wihongi’s case.
672R v Erstich (2002) 19 CRNZ 419 (CA); and R v Wihongi HC Napier CRI-2009-041-2096, 30 August 2010 [Wihongi (HC)]; R v Wihongi [2011] NZCA 592, [2012] 1 NZLR 775 [Wihongi (CA)]; and R v Wihongi [2012] NZSC 12 [Wihongi (SC)].
673At paragraph [2.11].
674The partial defence of provocation was available until December 2009 when it was repealed by the Crimes (Provocation Repeal) Amendment Act 2009.
675Tikiahi Erstich was initially sentenced in the High Court to a sentence of two years’ supervision with special conditions: R v Erstich, above n 672.
676At paragraph [3.31].
677For Ms Wihongi, this follows from the conviction for murder, while in Tikiahi Erstich’s case, the sentencing Judge acknowledged the jury’s verdict “may have reflected acceptance of lack of intent to murder” but observed it “was more likely on the facts of the case to have entailed the jury’s acceptance of the partial defence of provocation”: R v Erstich, above n 672, at [2].
678At [27].
679Wihongi (CA), above n 672, at [88].
680At [98].
681While infanticide and killing pursuant to a suicide pact (Crimes Act 1961, ss 178 and 180) are available as pathways to lesser convictions in certain narrow groups of cases that would otherwise meet the criteria for murder, there are no general partial defences in New Zealand. For the purposes of this Report, we largely disregard infanticide and killing pursuant to a suicide pact. As Warren Brookbanks has noted, they are closely circumscribed (infanticide) and rarely engaged (killing pursuant to a suicide pact): Warren Brookbanks “Partial Defences to Murder in New Zealand” in Alan Reed and Michael Bohlander (eds) Loss of Control and Diminished Responsibility: Domestic, Comparative and International Perspectives (Ashgate, Farnham, 2011) 271 at 271. They are also not relevant in cases where victims of family violence kill abusers. We refer to infanticide insofar as it may be some precedent for a separate homicide offence for victims of family violence but not otherwise.