R. v. Ferrari, 2012 ONCA 399 finds that, where the special mens rea requirements for murder are met, a person can be found guilty of first degree murder as a party to the offence:
(b) Party Liability under s. 21(2)
 The appellants submit that a person cannot be found guilty of first degree murder under s. 231(5) where their liability for murder rests on s. 21(2). Section 21(2), the provision imposing party liability for offences arising out of a common intention, provides as follows:
Where two or more persons form an intention in common to carry out an unlawful purpose and to assist each other therein and any one of them, in carrying out the common purpose, commits an offence, each of them who knew [or ought to have known] that the commission of the offence would be a probable consequence of carrying out the common purpose is a party to that offence. [Brackets added.]
 I have bracketed the phrase “or ought to have known” because the Supreme Court of Canada has held that to comply with the principles of fundamental justice in s. 7 of the Canadian Charter of Rights and Freedoms, an individual cannot be found to be a party to murder on the basis of objective foresight of death. As Lamer C.J. held in R. v. Rodney,  2 S.C.R. 687, at p. 692: “A party to a murder, therefore, cannot be convicted upon proof that he ought to have known that the murder was a probable consequence of carrying out the common purpose.” Thus, where, as here, the Crown relied upon s. 21(2) in a murder prosecution, it first had to prove that the appellants formed a common intention to carry out an unlawful purpose, for example, robbery or unlawful confinement, and that they assisted each other in carrying out the robbery or unlawful confinement. Second, the Crown had to prove that one of the appellants committed murder. Third, it had to prove that the other person (the participant or non-shooter) knew that the principal offender would probably commit murder in carrying out the unlawful purpose. This requirement of subjective foresight is crucial: see R. v. Laliberty (1997), 117 C.C.C. (3d) 97 (Ont. C.A), at pp. 107-108. In the context of this case, the non-shooter had to know that the shooter would probably cause the death of the deceased with one of the intents set out in s. 229(a) of the Code: either the intent to cause death, or the intent to cause bodily harm that the principal knew would likely cause death, being reckless whether death ensued or not.
 The appellants submit that while an individual may be found guilty of second degree murder by resort to s. 21(2), as modified by the Supreme Court of Canada to require subjective foresight, that provision cannot be the basis for liability for first degree murder. The submission is based on the following propositions. First, if the jury has resorted to s. 21(2), they must have rejected liability under s. 21(1), which requires an act, omission or encouragement. Second, s. 21(2) is essentially based upon mental elements—formation of an intention in common, an intention to assist and knowledge that the principal offender would probably commit murder—that are inconsistent with the kind of active participation required by the causation requirement for s. 231(5): actions that are an “essential, substantial and integral part of the killing of the victim”. This latter part of the argument is fortified by this court’s decision in R. v.
Section 21(2) must be distinguished from s. 21(1). The latter section is aimed at those who participate in the actual offence for which liability is imposed. Section 21(2) widens the circle of criminal culpability to include those who do not participate in the alleged crime but who do engage in a different criminal purpose and foresee the commission of the alleged offence by a party to that criminal purpose as a probable consequence of the pursuit of the criminal purpose: see R. v. Simpson (1988), 38 C.C.C. (3d) 481 at pp. 488-91, 46 D.L.R. (4th) 466,  1 S.C.R. 3. [Emphasis added.]
Where, however, liability is based on s. 21(2), there is no participation in the act which caused death but rather foresight that another would commit such an act. Culpability for the incidental offence flows almost entirely from foresight that that offence would be committed by another. [Emphasis added.]
 From the point of view of moral culpability or blameworthiness, an essential aspect of first degree murder, liability can be based upon s. 21(2). Justice Cory made this clear in Harbottle at p. 322:
Many if not all of the concerns expressed by the courts in the earlier cases have been eliminated by recent decisions of this Court. The concern that first degree murder should not apply to s. 21(2) parties to a murder who lacked any subjective foresight of death has been resolved by R. v. Rodney,  2 S.C.R. 687, and R. v. Logan,  2 S.C.R. 731. The unlawful object and felony murder provisions, another source of concern, were struck down or rendered moribund in R. v. Martineau,  2 S.C.R. 633. Thus the danger of an accused's becoming subject to a first degree murder sentence in the absence of subjective blameworthiness has effectively disappeared. The earlier cases were primarily concerned with the harshness that would arise from applying a broad causation rule to parties to an offence. In my view, that cause for concern no longer exists. [Emphasis added.]
 However, the fact that a s. 21(2) party may have the requisite blameworthy state of mind to warrant a conviction for first degree murder does not answer the question of whether such a party sufficiently participated in the killing. As Arbour J. said in Nette at para. 62:
The degree of participation in the killing by a party whose liability for murder is based on aiding or abetting under s. 21(1)(b) or (c) of the Criminal Code or common intention under s. 21(2) of the Code, may, under the Harbottle formulation, be insufficient to permit a finding that the murder amounts to first degree under s. 231(5), which requires that the murder be committed "by that person" in the course of committing the underlying offence.
 The question of s. 21(2) party liability was not squarely before the court in either Harbottle or Nette. The accused in Harbottle was either a co-perpetrator in the killing or a s. 21(1)(b) or (c) party. Nette was concerned with causation for second degree murder. There has been some judicial consideration of s. 21(2) by appellate courts since Harbottle. The New Brunswick Court of Appeal briefly dealt with the issue in R. v. Michaud (2000), 144 C.C.C. (3d) 62, at para. 14:
During oral argument, we drew counsel's attention to R. v. Harbottle,  3 S.C.R. 306, 84 C.C.C. (3d) 1, a case which, curiously enough, was cited neither in the appellant's nor in the respondent's written submission. In Harbottle, the Supreme Court of Canada adopted the view that the question of causation under s. 214(5) (now s. 231(5)) does not require a determination of who is a party to the commission of a particular offence under s. 21 of the Code. Rather, s. 231(5) requires that the Crown prove, beyond a reasonable doubt, that the victim's death was substantially caused by the accused, a burden that is met only where the evidence supports a finding that the accused played a very active role -- usually a physical role -- in the killing. Section 231(5) imposes criminal liability when the actions of the accused are shown to have formed "an essential, substantial and integral part of the killing of the victim". That being so, s. 21(2) cannot be a source of criminal liability for first degree murder. [Emphasis added.]
 I note that the Crown conceded on the appeal in Michaud that s. 21(2) could not be combined with s. 231(5): see para. 15. On the other hand, in R. v.
The appellants argue that the trial judge failed to adequately instruct the jury as to the degree of participation required for first degree murder pursuant to s. 231(5)(e) of the Criminal Code.
The trial judge's charge carefully tracked the five-step approach to s. 231(5) set out by the Supreme Court of Canada in R. v. Harbottle (1993), 157 N.R. 349; 66 O.A.C. 358; 84 C.C.C. (3d) 1, at 14.
In dealing with s. 231(5), the trial judge told the jury that in order to find the accused guilty of first degree murder, it was necessary for the Crown to establish beyond a reasonable doubt the underlying crime of domination, that is forcible confinement. He continued:
The person must be guilty of the forcible confinement. The accused must also be guilty of murder by being a party, either committing it or aiding or abetting it or being a party by subsection (2) of 21. The accused must have been shown to have participated - and this is the crux of it - in the murder in such a manner that he was the substantial cause of the death of the victim.
In my view, the trial judge's instruction was proper and I see no merit to this ground of appeal.
 However, a review of the factums filed in
Counsel on appeal argued that those two sections [ss. 21(2) and 231(5)] cannot be combined to found liability for first degree murder. We regard this as an open question of law. We also conclude that if the trial judge was wrong in combining the two sections as a basis for committal, the error was one of law rather than jurisdiction. Ultimately, the question on this appeal is whether there was a basis in the evidence upon which the justice could commit for trial on first degree murder.
 Thus, despite this court’s decision in
 It is true, as this court pointed out in
 An example can make the point more clearly. As I discuss at greater length below, in Harbottle, Cory J. gave some examples of where an accused could be convicted of first degree murder under s. 231(5). One example was described in the following terms at p. 324:
For example, if one accused with intent to kill locked the victim in a cupboard while the other set fire to that cupboard, then the accused who confined the victim might be found to have caused the death of the victim pursuant to the provisions of s. 214(5) [now s. 231(5)]. [Emphasis added.]
 In my view, liability under s. 231(5) would also flow if the one accused (the party), while not intending to kill the victim, knew that the principal offender would probably commit murder in carrying out the unlawful purpose, i.e., had the s. 21(2) mens rea for murder.. The participation by the party is the same whether the party intended to kill or merely knew that the principal offender would probably commit murder. Further, these acts of participation were a substantial cause of the death of the victim. I find it difficult to conceive that such a person would not have the requisite moral blameworthiness for first degree murder. Of course, a slight change in the facts might relieve the party of liability for first degree murder. If the victim was able to get out of the cupboard and was then shot by the principal offender, the acts of the party in confining the victim would not be a substantial cause of the death and the party would be guilty, at most, of second degree murder.
 When addressing potential liability for first degree murder, regardless of the basis upon which an accused may be guilty of murder, the trial judge must clearly focus on the additional elements of first degree murder as defined in s. 231(5) and relate the evidence to those elements. The jury must clearly understand in the context of the evidence it heard what it takes to make the accused guilty of first degree murder under s. 231(5).