- In a recent report, “Joint Enterprise ” the Commons Justice Select Committee recognised particular problems with the operation of the common law doctrine of joint enterprise and murder. The Committee was sympathetic to criticism of the complexity, lack of clarity, and inconsistent application of the doctrine, and recommended statutory reform. The operation of the doctrine and murder is particularly important because a conviction carries the highest sentence in the English penal system, mandatory life imprisonment.
- Joint enterprise is a parasitic form of secondary liability that arises with the commission of collateral offences during the course of a criminal venture.
- The common law doctrine of joint enterprise murder is set out in Powell and Daniels  1 A.C.1. If D1 and D2 had a common intention to commit crime A, where D1, as an incident of committing crime A, committed a collateral crime (crime B) involving fatal violence, if D2 had foreseen the possibility that D1 might do so intentionally, then D2 is complicit and shares criminal liability for murder.
- Two defences are available. The first is that the defendant had made a clear and unambiguous withdrawal before the incidence of violence took place. The second is the fundamentally different rule. This rule states that if the escalation of violence supersedes what was foreseen, it takes it outside the scope of any initial agreement (See Rahman  UKHL 45).
- It is notorious that a high proportion of homicides are not committed single-handed. Criminal law needs a coherent theory for punishing complicity when a criminal venture leads to fatal violence.
- The rationale can be summarised as this:
- Those who engage in criminal activity aware of the risk of serious violence must be held accountable. Engagement when aware of the risk of violence, implicitly or explicitly encourages it.
- It would be unacceptable for D2 to avoid liability for collateral offences of violence for lack of intent, when he has consciously accepted the risk of serious violence.
- There are also practical evidential considerations for the doctrine. Without a doctrine of complicity, there is a danger that enrolling other participants in a criminal enterprise could protect the perpetrator by creating collective immunity. If only the perpetrator can be liable, an evidential deficit could limit the courts ability to identify his role from among the participants. Cutthroat defences or walls of silence could successfully operate as a cloak of protection to joint criminality, despite high collective and individual culpability.
- In their report, the Committee also recognised a significant policy reason behind the doctrine, deterring the growth of gang related violence. They recognised that the courts intended to discourage young people, who may be on the periphery of gang related activity, from becoming involved in criminality .
- The current common law doctrine establishes a lower threshold for liability than for other parties involved in murder. The mental element required for complicity is that D2 foresaw that D1 might intentionally use serious violence. Foresight of a possibility can be described as a suspicion.
- A principal can only be found guilty of murder if he intended to kill or cause really serious harm.
- A secondary party who encouraged or assisted an offender, without being a party in the specific criminality, can only be found guilty of murder if he had knowledge or belief that the perpetrator would commit the offence (See Johnson and Youden  1 K.B. 544). Recent Court of Appeal judgments are inconsistent with this authority and appear to dilute the knowledge element in accessorial liability. However, they still set a higher standard of foresight, a real or substantial risk (See Bryce  EWCA Crim. 1231)
- A principal requires intent, an accessory requires knowledge, yet a complicit party requires suspicion. There is a clear lacuna between these standards. A conviction for complicity is founded on a bases that would not suffice to convict the principal nor an accessory.
- The doctrine does not reflect differences in culpability. It attaches liability to D2 for foreseen but unintended consequences. D1 murdered intentionally, yet D2 can share culpability for mere presence with suspicion. The significance here is that the disparity of culpability is not reflected in punishment. In a case of murder there is limited discretion within the mandatory sentencing regime.
- A precursor for joint enterprise liability is the need to establish an agreement between the parties, whether explicit or implicit, to carry out a crime. The agreement often can only be derived from perceived shared intentions evidenced by joint activity. Foresight of any risk can then be imputed to knowledge of the perpetrator and, as an inference from the agreement. The danger here is that the ambit of the doctrine could extend to guilt by association. For example: If D2 was a known associate of D1, who drove D1 to the scene, was present at the scene, and subsequently left with D1, even without evidence of direct participation, a jury could be asked to conclude that D2 was complicit. The circumstances are undoubtedly suspicious. However, a jury may find it difficult to distinguish between evidence of an implicit agreement and a suspicion, that is sufficient to associate the defendant with the crime, and evidence simply of association with the person who carried out the crime. This associational risk is highest for more peripheral parties to a crime.
- A jury might need assistance with evidence limited to association. As in other problematic areas of evidence they could be advised of the need for caution before convicting, be reminded of the evidences weaknesses and have specific evidence identified that could support both an agreement and suspicion.
- As the doctrine sets a low mental element required for liability, special care should be taken to ensure that a jury does not inadvertently apply objective standards of foresight or awareness. The common law has generally moved towards reinforcing subjective standards of mens rea. In joint enterprise murder, where the potential sentence is life imprisonment, the argument for reinforcing this standard is particularly strong.
- The civil courts have distinguished between subjective and objective standards of suspicion when considering the mental element for accessorial liability in trust law. They identified the following categories:
- Actual knowledge;
- Wilfully shutting one’s eyes to the obvious;
- Wilfully and recklessly failing to make such inquiries as an honest and reasonable man would make;
- Knowledge of circumstances which would indicate the facts to an honest and reasonable man; and
- Knowledge of circumstances which would put an honest and reasonable man on inquiry.
Only the first and arguably the second and third are subjective standards. However, a jury could interpret suspicion to include all five.
- Evidence at trial often focuses on knowledge of the murder weapon, and circumstantial evidence of association. If evidence is presented along the lines that the defendant must have foreseen the risk, the standards listed above become blurred. This criticism was raised in evidence before the Committee that “although the standard of D2’s fault is in theory a subjective one, the practical reality of a jury trial is that it has become objective” .
- When the jury are asked to determine D2’s mental state, if he realised that D1 might intentionally use serious violence, they might benefit from clarification. A subjective standard would require two questions:
- Whether the honest and reasonable man in D2’s situation would have realised the risk; and
- Whether D2 himself actually realised the risk.
- A conclusion that the defendant must have known should not be sufficient to incur such high liability. That approach may not sufficiently accommodate the individual characteristics of D2. This point becomes more important in gang related prosecutions where considerations of age, inexperience, intellect, naivety, or trust may be relevant considerations.
- A doctrine criticised for complexity, clarity and inconsistency would appear incompatible with the Rule of Law and would not accord with popular perceptions of justice. The justification for such a compromise appears to resolve around deterrence, particularly of gang activity.
- The necessary elements of an effective deterrent must include punitive credibility, clear and comprehensible definition, and widespread dissemination. The problem here is the latter two of these. It is not obvious that a doctrine subject to so much academic and legal debate is widely known yet alone understood by those who it seeks to deter. Conversely, a lack of knowledge or misunderstanding can lead to perceptions of malicious persecution and injustice that corrode confidence in the criminal justice system or society at large. This sense of social dislocation may inadvertently foster rather than deter gang mentalities.
- The current scope of the doctrine extends liability to an extent that creates a potential disproportional disconnect between culpability and punishment . Such a disconnect must be considered draconian. Statutory reform may assist if it provides sentencing flexibility. However, the issues of complexity and clarity also need to be resolved. If the knowledge and experience of the courts cannot assist juries by clarifying the doctrine’s ambit and interpretation, then parliament must try.