An unlawful cannot attract criminal liability without a sufficient level of awareness of the wrongfulness of the act. In legal terms the accused must have sufficient mens rea to be guilty of a crime. This manifests itself by either an intent on the part of the accused to choose to act in the unlawfulness or a knowledge of the circumstances under which they act to be held responsible for the offence.
However, it must be kept in mind that the latin maxim cogitationis poenam nemo patitur ("no one suffers punishment for mere intent") sets the principle that we not seek to punish people for their thoughts. So the awareness by itself cannot sustain a conviction without an action.
"Intent" refers to the mental state of the individual consisting of the desire or purpose to achieve a particular consequence, or where the consequences the person sees as certain, "substantially", or "practically" certain.
There is a presumption that Parliament drafts an offence expecting to require a subjective fault element.
The use of phrase such as "for the purpose of" found in the Code will sometimes refer to the "desire" or "ultimate objective or goal" of the prohibited act.
The presence of the word "wilfully" in an provision for an Criminal Code offence "generally signals a subjective mens rea requirement, but the appropriate meaning of the term ‘wilfully’ will depend on the context in which it is found." In context of a probation order, "wilful" denotes "a legislative concern for a relatively high level of mens rea" that requires a intent to breach and have a purpose in doing so.
- R v W.(A.), 2012 ONCJ 472 (CanLII) includes a very detailed consideration of the history of intent
R v Tatton, 2014 ONCA 273 (CanLII), at para 18
R v A.D.H., 2013 SCC 28 (CanLII), 2013 SCC 28, 358 D.L.R. (4th) 1, at para 23
R v Berhe, 2011 ONSC 6815 (CanLII) at para 32
- R v A.D.H.,  S.J. No. 5 (C.A.)
- R v Docherty, 1989 CanLII 45 (SCC),  2 SCR 941 at para 13
Specific and General Intent
A crime is only committed where the prohibited act or omission is committed while the accused is in possession of a requisite intent.
Absent words to the contrary in the Code, the presumption is that the offence is one of general intent, whereby the accused must have intended the act or omission.
Criminal law recognizes a distinction between offences that require specific and general intent as an essential element of proof. The difference concerns whether the intent applies "to the acts considered in relation to their purposes" (specific intent) or applies "to acts considered apart from their purpose" (general intent). General intent requires only intent as it "relates solely to the performance of the act in question", while specific intent involves "the performance of the actus reus, coupled with an intent or purpose going beyond the mere performance of the questioned act."
There is some acceptance that the distinction may not always be "logically defensible" and may produce "illogical results".
Most crimes where no mental element is mentioned in the definition of the offence will require proof of intent to or recklessness in bringing out the resulting offence.
Offences with the wording of "wilfully" suggests that the mens rea is extended to a "specific intent". 
It has been pointed out that the distinction between general and specific intent is "not particularly helpful in describing the actual mental elements required for a crime”. The can however convey "the complexity of thought and reasoning" and the "social policy underlying the offence.”
- R v Daviault, 1994 CanLII 61 (SCC),  3 SCR 63 per Cory J. ("...as early as the twelfth century, in large part through the influence of the canon law, it was established that there must also be a mental element combined with the prohibited act to constitute a crime. That is to say that the accused must have meant or intended to commit the prohibited act.")
e.g. R v Greenshields, 2014 ONCJ 35 (CanLII) at paras 10 to 18
R v MacDonald, 2014 SCC 3 (CanLII)
R v Bernard, 1988 CanLII 22 (SCC),  2 SCR 833 at para 61
R v George, 1960 CanLII 45 (SCC),  SCR 871, at p. 877
R v Tatton, 2014 ONCA 273 (CanLII), at para 34
Bernard at pp. 879 to 880 [SCR]
R v B.(S.J.), 2002 ABCA 143 (CanLII)
- R v Buzzanga and Durocher, 1979 CanLII 1927 (ON CA), (1979), 25 O.R. (2d) 705, 101 D.L.R. (3d) 488 (C.A.) at p. 717
- The Queen v Rees, 1956 CanLII 60 (SCC),  SCR 640
- R v Tatton, 2015 SCC 33 (CanLII) at para 35 per Moldaver J.
Intent is often proven by way of inference, including by use of circumstantial evidence, character evidence (e.g. motive or animosity), post-offence conduct, statements made by the accused, or similar fact evidence.
Inferences are factual findings based on common sense.
There is the long-standing inference that a person intends the natural consequences of one’s actions applies to many situations.
The inference will be made in most any circumstances except where there may be evidence to the contrary. Doubt may be raised as to the specific intent of the person where they suffer from mental illness or where intoxicated.
Generally speaking, the inference requires the assumption that the accused has the capacity to form intent.
Where circumstantial evidence is used to prove intent, there are three classes of circumstantial evidence:
- prospectant (acts or omissions prior to offence);
- concomitant (acts or omissions at the time of offence); and/or
- retrospectant (after the fact acts or omissions).
see R v Barbour, 1938 CanLII 29 (SCC),  SCR 465
R v Cloutier, 1979 CanLII 25 (SCC),  2 SCR 709
R v Lewis, 1979 CanLII 19 (SCC),  2 SCR 821
- see R v Daley, 2007 SCC 53 (CanLII) at paras 103 and 104
R v EB  OJ No 1864 aff'd at 2011 ONCA 194 (CanLII), at para 66 (context of murder)
R v Missions, 2005 NSCA 82 (CanLII) at para 21
R v Bergeron, 2015 BCCA 177 (CanLII) at paras 21 to 22 ("It is well established that a trier of fact is entitled to draw the common sense inference that a sane and sober person intends the natural and probable consequences of their actions.")
R v Starratt (1971), 1971 CanLII 541 (ON CA), 5 CCC (2d) 32 (ONCA) at para 3
See R v Giannotti (1956), 1956 CanLII 160 (ON CA), 115 CCC 203 (Ont. C.A.)
R v Hilson (1958), 1958 CanLII 134 (ON CA), 121 CCC 139 (Ont. C.A.)
R v Berger (1975), 27 CCC (2d) 357 (BCCA) (*no CanLII links) , leave to appeal to S.C.C. refused  SCR vii
R v Borque,  4 CCC 358, 7 C.R.N.S. 189 (BCCA)(*no CanLII links)
R v Theroux,  S.C.J. No. 42, 1993 CanLII 134 (SCC),  2 SCR 5,79 CCC (3d) 449 at 458 per McLachlin J.
R v Gill, 2012 ONCJ 326 (Ont. C.J.)(*no CanLII links) per Ready J.
R v Robinson, 2010 BCSC 368 (CanLII) at para 107
cited in R v Damin, 2011 BCSC 723 (CanLII) at para 33
R v McConnell, 2012 ABQB 263 (CanLII)
R v Seymour,  2 SCR 252, 1996 CanLII 201 (SCC) per Cory J
- See R v Bird (1973), 13 CCC (2d) 73 (Sask C.A.)(*no CanLII links)
R v Radita, 2017 ABQB 128 (CanLII), per Horner J, at para 160
R v Bottineau, 2006 CarswellOnt 8510 (ONSC)(*no CanLII links) , per Watt J, at para 62
Intending the Consequences of an Act
It has long been established that "a person who foresees that a consequence is certain or substantially certain to result from an act which he does in order to achieve some other purpose, intends that consequence." This is an inference, not a presumption. Its purpose is to determine intent in fact, and not to affix an intent based on reasonableness.
Thus, the purpose of the accused's action does not have to be to achieve the consequences in order to "intend" those consequences. The accused may very well not desire the consequences but still "intend" them where "he foresees that the consequence is certain or substantially certain to result from his conduct"
An "ulterior motive" does not need to be directly related to the consequences.
R v Buzzanga and Durocher (1979), 1979 CanLII 1927 (ON CA), 49 CCC (2d) 369 (ONCA) at p. 383-4 [CCC]
R v MacKinlay, 1986 CanLII 111 (ON CA)
e.g. R v Farrant, 1983 CanLII 118 (SCC),  1 SCR 124
R v Seymour, 1996 CanLII 201 (SCC),  2 SCR 252 at para 20
- MacKinlay, supra
R v Iyanam, 2013 ONSC 1091 (CanLII) at para 23 to 27
- Iyanam, ibid. at para 26, 27
- e.g. Iyanam, ibid. at para 22
The common law doctrine of transferred intent will impose a necessary mens rea for a conviction for an act with unintended consequences. Where "harm follows that is of the legal kind as that intended" the accused will have been deemed to have intended the act.
Section 229(b) of the Criminal Code adopts transferred intent as a form of liability for murder.
229. Culpable homicide is murder...
- (b) where a person, meaning to cause death to a human being or meaning to cause him bodily harm that he knows is likely to cause his death, and being reckless whether death ensues or not, by accident or mistake causes death to another human being, notwithstanding that he does not mean to cause death or bodily harm to that human being;
R.S., c. C-34, s. 212.
The doctrine of tranferred intent does not apply for attempted murder.
- R v Gordon, 2009 ONCA 170 (CanLII) at para 42
- Gordon, ibid. at para 78
- see Recklessness
The inference of intending consequences of one's act must be considered after assessing "all of the evidence, including the evidence of intoxication".
Intoxication is only relevant insofar as it affects "the accused's capacity to form the requisite intent" to commit the offence.
Where evidence shows that the accused acted involuntary due to intoxication, negating intent on a general intent offence, proof of voluntary intoxication may in certain cases substitute for proof of voluntariness. This "Leary rule" of substitution is typically available to offences of any general intent offence. This was not considered applicable to assault based offence including sexual assault. As a result s. 33.1 was enacted removing the intoxication defence from certain offences.
- R v Seymour, 1996 CanLII 201 (SCC),  2 SCR 252
- R v Robinson, 1996 CanLII 233 (SCC),  1 SCR 683
R v Tatton, 2014 ONCA 273 (CanLII), at para 35
R v Bernard,  2 SCR 833, 1988 CanLII 22 (SCC), at pp. 878-879 [SCR]
Bernard, ibid. at para 73
R v Daviault, 1994 CanLII 61 (SCC),  3 SCR 63
Examples of Intent
Intent to Kill
In absence of any explanation, the only intent from firing a gun at a person is an intention to kill.
R v McArthur, 2013 SKCA 139 (CanLII), at para 11