A Unitary Theory of Perpetration? New Zealand and a Touch of the International

Sir David Baragwanath is a Judge at the Special Tribunal for Lebanon, and was President of that court between 2011 and 2015. Before this, he sat as a judge of the High Court and the Court of Appeal of New Zealand. He was made a knight companion of the New Zealand order of merit. It is a great honor to host such a distinguished compatriot here.


This paper considers concepts of unitary theory of perpetration in relation to New Zealand domestic law and touches on aspects of international criminal law.  It argues:

  • that New Zealand law adopts in s 66(1) of its Crimes Act 1961 a dilute unitary approach (from which a divided Supreme Court in Ahsin v The Queen [2014] NZSC 153 has recently created a partial exception) and in s 66(2) a mixed unitary and non-unitary approach. It may be expected that New Zealand will prefer the recent UK Supreme Court and Privy Council decisions in R v Jogee [2016] UKSC 8 [2016] UKPC 7, which accord with the language of s 66(2), to the decision of the High Court of Australia in Miller v The Queen [2016] HCA 30 which preferred the approach of R v Chan Wing-Siu [1985] AC 168(PC) which, having been as accepted for 30 years as stating English law, was rejected in Jogee;
  • that the decision of the Special Tribunal for Lebanon in Interlocutory Decision on the Applicable Law STL-11-01/I 16 February 2011 (STL Casebook 2011 pp167-8, 177 and 182) paras 227, 248-9 and 259 n 381) in relation to terrorism (at para 249) conforms with Jogee by rejecting JCE III for crimes of specific intent;  other cases cited (para 239) adopt the more rigorous approach of a form of  JCE III which conforms with Chan Wing-Siu but not with the Statute of the STL.

The New Zealand statute

New Zealand criminal law is codified by the Crimes Act 1961 which states:

Part 4 Parties to the commission of offences

66 Parties to offences

(1) Every one is a party to and guilty of an offence who—

(a)  actually commits the offence; or

(b)  does or omits an act for the purpose of aiding any person to commit the offence; or

(c)  abets any person in the commission of the offence; or

(d)  incites, counsels, or procures any person to commit the offence.

(2) Where 2 or more persons form a common intention to prosecute any unlawful purpose, and to assist each other therein, each of them is a party to every offence committed by any one of them in the prosecution of the common purpose if the commission of that offence was known to be a probable consequence of the prosecution of the common purpose.


In Alan Reed and Michael Bohlander’s Participation in Crime: Domestic and Comparative Perspectives,[2] Julie Tolmie of the University of Auckland gives a valuable overview of the New  Zealand perspective.

S66(1), as far as it goes, applies what James Stewart terms “a watered down unitary concept”: “criminal legislation [that] … articulates the different forms of causal connections that might apply within a unitary framework” and, unlike any example of  his pure unitary theory”, “does … forewarn would-be  criminals of their exposure to potentially serious criminal responsibility” and so not “violating  the principle of legality.”[3]  Both the “person who actually commits the offence” and all who “aid…, abet, incite, counsel or procure” the offence are party to and guilty of it.  All are factual contributors, in different ways, to the very same crime.  Each personally commits an act which in fact is causally connected to achieving the crime.

S66(2) provides a further pathway to liability for an offence by the one, who in the language of s66(1)(a), actually commits the offence,  on the part of all others who fall within the scope of s 66(2).

S66(2) constitutes in part a unitary offence – a single offence, to which all liable for it are regarded as parties. But in part it is not unitary: liability of Parties B1-B? for the offence committed by Party A does not derive from their factual contributions, in different ways, to the very same crime.  It is not necessary that, as in the case of s 66(1), each personally commits an act which in fact is causally connected to achieving the crime.   Instead S 66(2) imputes to Parties B –B? a legal vicarious liability for the offence Z of A, on account of (1) their being party with A to a common purpose (say bank robbery) which they share with him ( to commit that offence ), coupled (2) with their knowledge that his committing a different offence (say murder) is a probable consequence.

It should be added that in Ahsin the New Zealand Supreme Court, reversing Court of Appeal authority, held that s 66(2) imposes liability both for the robbery/ murder case just mentioned and also for a single offence the object of some common purpose. I respectfully disagree with that conclusion, based on a purely verbal reference to the words “common purpose” that can literally embrace the case of a single crime.    But the context does not permit that conclusion.    The “common purpose” is to commit a crime.  Once that element is established and the crime is committed the case under S66(1) is complete.  There is simply no reason to have s66(2) apply to that crime.  Its function is to impose liability for a second and distinct crime where the elaborate further mens rea condition is proved.  Ahsin unnecessarily complicates the clear and simple language of the statute.

There is a striking contrast with such non-unitary jurisdictions as Germany and Lebanon, whose Criminal Code distinguishes sharply between “the perpetrator of an offence” (Criminal Code Art 212) and others, such as “an accomplice”(Art 213) and “an instigator” (art 217).

Cassese writing extrajudicially pointed out that in international criminal law

…although it is not strictly required by any of the statutes of the modern international criminal courts, the judicial practice has been to classify every charge and conviction by mode of liability. Thus, the discussion of the modes of liability – whether it is, for example, commission, aiding and abetting, ordering, or command responsibility – is a focus of almost every judgment. [4]

Yet unless the law so requires, this complication of  trial and adjudication, by the introduction to international criminal law of concepts of “modes of liability” not stipulated by legislation or required by any general principle of law, is unnecessary.  Its use may illustrate the old habit of lawyers to create imaginary goblins.  Familiar examples are the notion that there is some such thing – Kant’s ding an sich­, a real entity – as “possession”, or “a company”, beyond the legal result created by rules of law.  Each has been demolished by masters of jurisprudence; [5] it is time for the same to be done to modes of liability in jurisdictions that do not stipulate for them.  Otherwise international criminal procedure, already complex and expensive, adds to those problems by forcing itself to leap over self-created non-existent hurdles.

The following draws on Edmonds v The Queen [2011] NZSC 159 at [21ff] where William Young J described the history of the New Zealand legislation and provided a comparison with the laws of England and Wales.

The New Zealand Act derives its s66(1)(b)-(d) from s71 of the 1879 draft Code prepared by the Stephen Commission and s8 of the (current) Accessories and Abettors Act 1861 (UK), but there has been divergence between the English and New Zealand jurisdictions in relation to mens rea.  The New Zealand aiding and abetting cases require the Crown to establish that the secondary party intentionally helped or encouraged the principal offender with knowledge of the essential matters constituting the offence, including the principal’s mens rea.   Some English cases on aiding and abetting suggest that recklessness or foresight, rather than knowledge, is sufficient. [6]

As to s66(2), William Young J observed:

[23] The general common law principles of joint enterprise liability correspond closely to s 66(2).

Chan Wing-Siu, Jugee and Miller

A footnote then cites Chan Wing-Siu v R [1985] AC 168 (PC) and suggests that its author, Sir Robin Cooke, then President of the Court of Appeal of New Zealand and later a Law Lord, would have had s66(2) well in mind.  In fact its language, requiring that “the commission of that offence was known to be a probable consequence of the prosecution of the common purpose”  is more exacting than that required by Chan Wing-Siu.  There:

it was submitted for the appellants that it was not enough if an appellant foresaw death of grievous bodily harm as a possible consequence of the joint enterprise: that the jury ought to have been directed that it must be proved that he foresaw that one of those consequences would probably  result.

The former was held to suffice.

The citation from Edmonds continues:

It is, however, important to recognise that the common law status of joint enterprise liability principles means they are more susceptible to judicial development than s 66(2).

Given the leap in Chan Wing-Siu from the “probable consequence”of s 66(2) to the lesser “possible consequence” test adopted, the observation was correct.

After Chan Wing-Siu v R had been followed for three decades by English law, including R v Powell [1999] AC 1, [1997] UKHL 45, in R v Jogee [2016] UKSC 8 [2016] UKPC 7 a joint judgment of the UK Supreme Court and the Privy Council rejected Chan Wing-Siu v R.  It held that Party B is not guilty unless he acted with the same mental intent the law requires of Party A (Party B’s intent may be conditional –  agreement that if the occasion arose A’s crime would be committed: at para 94).

The High Court of Australia in Miller v The Queen [2016] HCA 30 has since declined to depart from the Chan Wing-Siu v R principle which it had previously endorsed. Recently, in HKSAR v Chan Kam Shing FACC No. 5 of 2016 , delivered on 16 December 2016, the Final Court of Hong Kong preferred the Cooke and High Court of Australia decisions to the UKSC and PC.

In Ahsin v The Queen [2014] NZSC 153 the majority of the Supreme Court at [92] and William Young J (concurring in part) at [240] cited Chan Wing-Siu v R without discussing the point later discussed in  Jogee and in Miller.  Elias CJ [20] and William Young J [245 ff] dissented from the view of the majority that an offence by an accessory party is complete when assistance is given, considering that the assistance or encouragement “must continue at the time of the commission of the offence.”   Such distinction was relevant to the debate in that case as to whether absence of  “withdrawal” is an element of the offence, to be excluded by the prosecution (minority view), or a substantive defence, requiring evidence of withdrawal before such issue is left to the jury (majority [120); Elias CJ [21]; William Young J [244 ff].   The majority opinion on these points entails a breach of the unitary principle in relation to s66(1)(b): unlike others charged under s66(1), those charged under that provision appear to be entitled to a defence of withdrawal which does not negate assistance previously provided: William Young J at [253].


The Special Tribunal for Lebanon is empowered by its Statute to apply to party liability either the criminal law of Lebanon (Article 2), with its non-unitary approach, or a formulation of international criminal law (Article 3).  In Interlocutory Decision on the Applicable Law its Appeals Chamber has held that the principle favor rei entitles the accused to select whichever is more favourable to the defence.

Article 3 of the Statute provides for individual responsibility if an accused either infringed Article 2 or:

… Contributed in any other way to the commission of the crimes set forth in Article 2 … by a group of persons acting with a common purpose, where such contribution is intentional and is either made with the aim of furthering the general activity or purpose of the group or in the knowledge of the intention of the group to commit the crime.

The emphasised passage does not justify application by the STL of a Chan Wing-Siu approach  There is some support however for such approach in cited decisions at international law.

In “The End of ‘Modes of Liability’ for International Crimes” (2012) 25 Leiden Journal of International Law 165 Professor Stewart mounted a particular challenge to JCE III.    I add to his reference to Antonio Cassese’s essay [7] the discussion of international criminal law in the judgment of the Appeals Chamber of the  Special Tribunal for Lebanon in Interlocutory Decision on the Applicable Law STL-11-01/I 16 February  2011 (STL Casebook 2011 pp167-8, 177 and 182) paras 227, 248-9 and 259 n 381) , requiring Party B to be aware either of the criminal intent of Party A or of the substantial likelihood that Party A will commit the crime.

There may be noted however the citation of “JCE III” decisions requiring only that the secondary offender “(i) was aware that the resulting crime was foreseeable  as a possible consequence of the execution of the JCE, and nonetheless (ii) willingly took the risk that the incidental crime might be committed and continued to participate in the enterprise with that subjective awareness”(p174 para 241).  That is pure Chan Wing-Siu. But the Appeals Chamber did not apply such principle to the case of specific intent crimes such as terrorism, holding:

249 … the better approach is not to allow convictions under JCE III for specific intent crimes like terrorism… He must have the required specific intent for terrorism; he must specifically intend to cause panic or to coerce a national or international authority [according to the STL AC’s definition of terrorism].

This is not the occasion to debate the topic of Chan Wing-Siu type JCE III, which is not permitted by the STL Statute.  Or whether a Chan Wing-Siu approach might be warranted in the case of a commander such as General Yamashita (cf In re Yamashita 327 US 1 (1946)).


The STL AC’s approach to international criminal law coincides with the NZ watered down unitary principle of s 66(1) and its mix of unitary and non-unitary approach in s 66(2).  It conforms with Jogee in the case of terrorism;  other cases of JCE III cited in the decision do not.


[1] KNZM  former Judge of the Court of Appeal of New Zealand, President of the New Zealand Law Commission, New Zealand Member of the Permanent Court of Arbitration;  Appellate Judge and past President the Special Tribunal for Lebanon, Overseas Bencher The Inner Temple

[2] Ashgate 2013

[3] James G. Stewart, Complicity, in Oxford Handbook of Criminal Law (Markus Dubber & Tatjana Hörnle eds., OUP 2014),  at 539-540.

[4] Cassese’s International Criminal Law (3ed Oxford 2013) 162

[5] “it is impossible to define a legal concept, and […] the task of legal writers should be rather to describe the use of a word like ‘possession’ in the particular legal rules in which it occurs. ‘Possession’ in the legal sense has no meaning at all apart from the rules of law in which it is used as a tool of legal thought.  “The Concept of Possession in English Law” by Professor D.R. Harris QC in Oxford Essays in Jurisprudence (ed AG Guest, Oxford 1961) 69 at 70 drawing on Bentham and HLA Hart.

Lord Hoffmann in Meridian Global Funds Management Asia Ltd v The Securities Commission (1995):

… a reference to a company “ as such” might suggest that there is something out there called a company of which it can be meaningfully said that it can or cannot do something.  There is in fact no such thing as the company as such, no ding an sich, only the applicable rules. To say that a company cannot do something means only that there is no one whose doing of that act would, under the applicable rules of attribution, count as an act of the company.

 [1995] UKPC 5, [1995] 2 AC 500 at [10]

[6] Eg R v Rook [1993] 1 WLR 1005 (CA) criticized by AP Simester “The Mental Element in Complicity” (2006) 122 LQR 578.

[7] Nn 25 and 56