Is a partial defence justified?
Conclusions and recommendation
10.108In this chapter we have considered the in-principle case for and against a partial defence or a separate homicide offence and the form any such defence or offence might take. We have sought to review the arguments and the options fairly and comprehensively, but for the following six reasons, we do not recommend that a partial defence or a specific offence be introduced in New Zealand:
- Although a number of arguments may be marshalled in support of partial defences, a mandatory sentence is their driving and most compelling rationale. In a jurisdiction, such as New Zealand, that has abolished mandatory murder sentencing, that rationale falls away. To the extent there are vestiges of mandatory sentencing (such as the three strikes law) or other problems with sentencing, it is preferable that they be addressed directly in that context.
- Partial defences are conceptually problematic. They are anomalous, as they apply only to homicide, and they introduce arbitrariness and rigidity into the recognition of mitigating circumstances. They are not the best way to recognise reduced culpability.
- The experience of partial defences in New Zealand and elsewhere bears out these conceptual problems. In whatever form and with whatever focus, partial defences have given rise to complexity and difficulties.
- It is well recognised that partial defences, and particularly excessive self-defence, can work to the detriment of defendants who seek to rely on self-defence. The recommendations we make in this Report are intended to work as a package, and we are concerned to avert any reform that might undermine the effectiveness of our recommended clarification of section 48 of the Crimes Act.
- As in previous Law Commission reports and in common with a number of overseas law reform bodies, commentators and submitters, we consider mitigating circumstances are best addressed at sentencing. We would only recommend a partial defence or new offence if there was evidence of a clear and strong need. We have not identified such evidence. Most victims of family violence who commit homicide are charged with murder but are convicted of manslaughter. As we discuss in the next chapter, in the rare case where a victim of family violence is convicted of murder, we consider the essential structure of New Zealand’s sentencing framework is capable of taking into account the mitigating circumstances of victims of family violence who commit homicide.
- Finally, our review is limited to victims of family violence and we have not had the opportunity (or a remit) to consider the position of homicide defendants generally. Even a carefully tailored partial defence, based on a criterion like trauma, would raise complexity, and there would be significant risks with limiting any defence to a narrow group of defendants.
10.109The centrepiece of our recommended legislative reforms is to make self-defence more accessible to victims of family violence who kill their abusers. Amendments to the Crimes Act will clarify that, in the context of family violence, self-defence may apply in the absence of an imminent threat. Whether the force used was reasonable will remain a question of fact for the jury.
10.110Cases where an offender has a history of being abused by the deceased but there is no viable claim of self-defence will involve some culpability, but it might be mitigated because of the history of abuse. In such cases, our view is that sentencing provides a better avenue than partial defences for addressing variation in homicide offending. This presumes the sentencing process is able to properly take into account the various factors that might mitigate culpability, however. In the next chapter, we consider the adequacy of New Zealand’s sentencing law in this context.
- R9 No new partial defence or separate homicide offence should be introduced in New Zealand.