As a matter of strict analysis there is, as Professor J.C. Smith pointed out in his commentary on Reg. v. Wakely  Crim. L.R. 119, 120, a distinction between a party to a common enterprise contemplating that in the course of the enterprise another party may use a gun or knife and a party tacitly agreeing that in the course of the enterprise another party may use such a weapon. In many cases the distinction will in practice be of little importance because as Lord Lane C.J. observed in Reg. v. Wakely, at p. 120, with reference to the use of a pick axe handle in a burglary, "Foreseeability that the pick axe handle might be used as a weapon of violence was practically indistinguishable from tacit agreement that the weapon should be used for that purpose." Nevertheless it is possible that a case might arise where a party knows that another party to the common enterprise is carrying a deadly weapon and contemplates that he may use it in the course of the enterprise, but, whilst making it clear to the other party that he is opposed to the weapon being used, nevertheless continues with the plan. In such a case it would be unrealistic to say that, if used, the weapon would be used with his tacit agreement. However it is clear from a number of decisions, in addition to the judgment of the Court of Appeal in Reg. v. Smith  1 W.L.R. 1200, that as stated by the High Court of Australia in McAuliffe v. The Queen (1995) 69 A.L.J.R. 621, 624 (in a judgment to which I will refer later in more detail) "The scope of the common purpose is to be determined by what was contemplated by the parties sharing that purpose." Therefore when two parties embark on a joint criminal enterprise one party will be liable for an act which he contemplates may be carried out by the other party in the course of the enterprise even if he has not tacitly agreed to that act.
The principle stated in Reg. v. Smith was applied by the Privy Council in Chan Wing-Siu v. The Queen  A.C. 168 in the judgment delivered by Sir Robin Cooke who stated, at p. 175G:
"The case must depend rather on the wider principle whereby a secondary party is criminally liable for acts by the primary offender of a type which the former foresees but does not necessarily intend.
"That there is such a principle is not in doubt. It turns on contemplation or, putting the same idea in other words, authorization, which may be express or is more usually implied. It meets the case of a crime foreseen as a possible incident of the common unlawful enterprise. The criminal culpability lies in participating in the venture with that foresight."
The principle stated by Sir Robin Cooke in Chan Wing-Siu's case was followed and applied in the judgment of the Court of Appeal in Reg. v. Hyde  1 Q.B. 134, where Lord Lane C.J. took account of Professor Smith's comment in Reg. v. Wakeley that there is a distinction between tacit agreement and foresight and made it clear that the latter is the proper test.
In Hui Chi-ming v. The Queen  1 A.C. 34 the Privy Council again applied the principle stated by Sir Robin Cooke in Chan Wing-Siu v. The Queen and in delivering the judgment of the Board Lord Lowry stated, at p. 53B:
"The defendant's second point relies on Sir Robin Cooke's use of the word 'authorisation' as a synonym for contemplation in the passage already cited from his judgment in Chan Wing-Siu v. The Queen  A.C. 168, 175. Their Lordships consider that Sir Robin used this word--and in that regard they do not differ from counsel--to emphasise the fact that mere foresight is not enough: the accessory, in order to be guilty, must have foreseen the relevant offence which the principal may commit as a possible incident of the common unlawful enterprise and must, with such foresight, still have participated in the enterprise. The word 'authorisation' explains what is meant by contemplation, but does not add a new ingredient. That this is so is manifest from Sir Robin's pithy conclusion to the passage cited: 'The criminal culpability lies in participating in the venture with that foresight.'"
In McAuliffe v. The Queen (1995) 69 A.L.J.R. 621 the High Court of Australia has recently stated that the test for determining whether a crime falls within the scope of a joint enterprise is now the subjective test of contemplation and the Court stated, at p. 624:
"Each of the parties to the arrangement or understanding is guilty of any other crime falling within the scope of the common purpose which is committed in carrying out that purpose. Initially the test of what fell within the scope of the common purpose was determined objectively so that liability was imposed for other crimes committed as a consequence of the commission of the crime which was the primary object of the criminal venture, whether or not those other crimes were contemplated by the parties to that venture. However, in accordance with the emphasis which the law now places upon the actual state of mind of an accused person, the test has become a subjective one and the scope of the common purpose is to be determined by what was contemplated by the parties sharing that purpose."
There is therefore a strong line of authority that participation in a joint criminal enterprise with foresight or contemplation of an act as a possible incident of that enterprise is sufficient to impose criminal liability for that act carried out by another participant in the enterprise.
I would add that, in my opinion, Lord Parker in Reg. v. Anderson; Reg. v. Morris  2 Q.B. 110, having accepted the principle formulated by Mr. Lane, made it clear in other parts of the judgment that he was not intending to depart from the principle in Reg. v. Smith, because immediately after stating Mr. Lane's formulation Lord Parker said at p. 119:
"In support of that, he refers to a number of authorities to which this court finds it unnecessary to refer in detail, which in the opinion of this court shows that at any rate for the last 130 or 140 years that has been the true position. This matter was in fact considered in some detail in Reg. v. Smith (Wesley), heard by a court of five judges presided over by Hilbery J., in which Slade J. gave the judgment of the court. Reg. v. Smith (Wesley) was referred to at some length in the later decision in this court in Reg. v. Betty; it is unnecessary to go into that case in any detail. It followed the judgment of Slade J. in Reg. v. Smith (Wesley), and it did show the limits of the general principle which Mr. Lane invokes in the present case. In Reg. v. Smith (Wesley) the co-adventurer who in fact killed was known by the defendant to have a knife, and it was clear on the facts of that case that the common design involved an attack on a man, in that case a barman, in which the use of a knife would not be outside the scope of the concerted action. Reference was there made to the fact that the case might have been different if in fact the man using the knife had used a revolver, a weapon which he had, unknown to Smith.
"The court in Reg. v. Betty approved entirely of what had been said in Reg. v. Smith (Wesley), and in fact added to it."
Later at p. 120B I consider that Lord Parker applied the test of foresight when he stated:
"It seems to this court that to say that adventurers are guilty of manslaughter when one of them has departed completely from the concerted action of the common design and has suddenly formed an intent to kill and has used a weapon and acted in a way which no party to that common design could suspect is something which would revolt the conscience of people today."
Therefore I consider that the judgment in Reg. v. Anderson was not intended to constitute a departure from the principle stated in Reg. v. Smith, and that the acceptance of Mr. Lane's test was regarded by the Court of Appeal as an alternative way of formulating the principle stated in Reg. v. Smith, although as Professor Smith has pointed out, as a matter of strict analysis, a distinction can be drawn between the two tests.
The second issue which arises on these appeals is whether the line of authority exemplified by Reg. v. Smith and Chan Wing-Siu is good law in the light of the decisions of this House in Reg. v. Moloney  A.C. 905 and Reg. v. Hancock  A.C. 455. In the latter case Lord Scarman, referring to Moloney, stated, at p. 471:
"First, the House cleared away the confusions which had obscured the law during the last 25 years laying down authoritatively that the mental element in murder is a specific intent, the intent to kill or to inflict serious bodily harm. Nothing less suffices: and the jury must be sure that the intent existed when the act was done which resulted in death before they can return a verdict of murder.
"Secondly, the House made it absolutely clear that foresight of consequences is no more than evidence of the existence of the intent; it must be considered, and its weight assessed, together with all the evidence in the case. Foresight does not necessarily imply the existence of intention, though it may be a fact from which, when considered with all the other evidence, a jury may think it right to infer the necessary intent. Lord Hailsham of St. Marylebone L.C. put the point succinctly and powerfully in his speech in Reg. v. Moloney  A.C. 905, 913: 'I conclude with the pious hope that your Lordships will not again have to decide that foresight and foreseeability are not the same thing as intention although either may give rise to an irresistible inference of such, and that matters which are essentially to be treated as matters of inference for a jury as to a subjective state of mind will not once again be erected into a legal presumption. They should remain, what they always should have been, part of the law of evidence and inference to be left to the jury after a proper direction as to their weight, and not part of the substantive law.'
"Thirdly, the House emphasised that the probability of the result of an act is an important matter for the jury to consider and can be critical in their determining whether the result was intended."
In reliance upon Reg. v. Moloney and Reg. v. Hancock Mr. Feinberg, on behalf of the appellants Powell and Daniels, submitted to this House, as he submitted to the Court of Appeal, that as a matter of principle there is an anomaly in requiring proof against a secondary party of a lesser mens rea than needs to be proved against the principal who commits the actus reus of murder. If foreseeability of risk is insufficient to found the mens rea of murder for a principal then the same test of liability should apply in the case of a secondary party to the joint enterprise. Mr. Feinberg further submitted that it is wrong for the present distinction in mental culpability to operate to the disadvantage of a party who does not commit the actus reus and that there is a manifest anomaly where there is one test for a principal and a lesser test for a secondary party.
A similar argument had previously been rejected by the Court of Appeal in Reg. v. Ward (1986) 85 Cr.App.R. 71 and in Reg. v. Slack  Q.B. 775. In Reg. v. Ward, Lord Lane C.J. stated, at pp. 76-77:
"It is submitted by Mr. Steer in regard to that ground of appeal that the decisions of the House of Lords in Reg. v. Moloney and Reg. v. Hancock have had the effect of completely altering the law relating to joint enterprise. The way in which he put it was this. We asked him to dictate the submission so we could write it down. No man, he submits, can be convicted of murder unless it is specifically decided against him that he had a murderous intent and that could only be decided against him if the judge directed the jury that that was what they had to find.
"Each member of this Court is bound to confess that he was unable to understand the submission. It is enough to say that we do not consider that the cases of Reg. v. Moloney and Reg. v. Hancock have had any effect at all upon the well-known and well-established principles of joint enterprise: in short, the principle set out in Reg. v. Anderson; Reg. v. Morris (1966) 50 Cr. App. R. 216,  2 Q.B. 110 still holds good . . .
"We are told that the learned judge may have been equipped with the opinion of the Judicial Committee of the Privy Council in a case called Chan Wing-Siu v. The Queen  A.C. 168. If that is so, the learned judge accurately reflected the view of their Lordships in that case in the passage which I have read.
"It was suggested by Mr. Steer that the decision in that case, which came from Hong Kong, is not in accordance with the decisions of the House of Lords in Reg. v. Moloney and Reg. v. Hancock. We disagree. We think that what appears in that case, if we may say so respectfully, is good law.
In Reg. v. Slack  Q.B. 775, Lord Lane C.J. stated, at p. 780:
"Chan Wing-Siu v. The Queen  A.C. 168 was considered and approved by this court in Reg. v. Ward (1986) 85 Cr. App. R. 71. The appellant's submission in that case was that the decisions of the House of Lords in Reg. v. Moloney  A.C. 905 and Reg. v. Hancock  A.C. 455 had the effect of completely altering the law relating to joint enterprise; that no man can be convicted of murder unless it is specifically decided against him that he had a murderous intent; since intent had to be read against the decisions in Reg. v. Moloney  A.C. 905 and Reg. v. Hancock  A.C. 455 the jury ought to be directed on the basis of those cases.
"This court in Reg. v. Ward (1986) 85 Cr.App.R. 71 reiterated the passage from Reg. v. Anderson; Reg. v. Morris  2 Q.B. 110, 118-119, cited above and went on to hold that Reg. v. Moloney  A.C. 905 and Reg. v. Hancock  A.C. 455 had had no effect on the well known and well established principles of joint enterprise."
As Lord Lane observed in Reg. v. Slack, p. 780H, difficulties had arisen from the judgment of the Court of Appeal in Reg. v. Barr (1986) 88 Cr.App.R. 362. It appears from the facts that violent acts by all three defendants, who were burglars, caused the death of the householder. The trial judge directed the jury as though it was not necessary for a defendant charged with murder to possess himself the necessary intent either to kill or do serious bodily harm to the victim: it was enough to convict him of murder if he contemplated that one of his co-defendants had one of these intents and that he foresaw the possibility of that intent being carried into effect by that person.
The Court of Appeal held that this was a misdirection and quashed the convictions, Watkins L.J. stating, at p. 369:
"where it is appropriate to direct a jury upon foreseeability of consequence, the jury must be told that evidence of such foreseeability does no more than assist the jury to determine whether a defendant had at the requisite time an intention either to kill or to do serious harm to the victim.
"Unwittingly, the judge with regard to a time prior to the burglary, unaided by those authorities, because they were decided after he had directed the jury in the present case, seems to have directed them as though it was not necessary for a defendant charged with murder himself to possess one of the necessary intents: it was enough to convict him if he contemplated that one of his co-accused had one of those intents and that he no more than foresaw the possibility of that intent being carried into effect by that person."