6. Voluntariness: automatism, duress, necessity and intoxication

One of the basic requirements of the criminal law is that one's acts have been voluntary. Voluntariness points to something even deeper than the mens rea, and should not be confused with willingness. It is sometimes considered as a sort of "mental element" of the actus reus itself, in the sense that you cannot even be said to have committed the act if you did not do so voluntarily. It suggests a basic concept of control over one's acts. Imagine, for example, simply falling on someone by accident: clearly the act was involuntary. A person may seem superficially to manifest intent, but in fact be engaged in an entirely involuntary conduct. Think for example of someone who is sleep walking. We have seen the special case of persons being found not criminally responsible by reason of mental disorder, but here we are interested in persons being fully acquitted because their acts were not even voluntary.

The non-voluntary character of behaviour can become more complicated when what is involved is not an automatism, but some external compulsion. If you are threatened with death unless you inflict bodily harm on someone, can your acts still be said to be voluntary? What about inflicting death to someone, less your little finger be broken? Is there an expectation of reasonable fortitude in the face of threats? Moreover, involuntariness might result from a self-inflicted condition, such as extreme intoxication. These and other questions go less to the physical control over one's acts than the deeper question of the libre arbitre.  If the criminal law presumes that one has to be free to commit criminal offences, then what does it mean to be free, or how free does one have to be? These are questions as old as the criminal law itself, but in the Canadian context they have been reenergized through Charter scrutiny.


We have already seen mental disorder automatism. But an automatism may arise outside a mental disorder. Imagine for example that you are driving and stung by a wasp and have an immediate, instinctive reaction which leads to an accident; or that you have a stroke and fall on a child; or that you kill someone as you sleepwalk. Automatism suggests something more than the inability to have the mens rea: like mental disorder, it suggests something closer to involuntariness. The law generally assumes that our acts are voluntary. Although this may seem to relieve the prosecution of the need to prove this beyond reasonable doubt, it seems justified given how likely it is that most of our acts are indeed voluntary. Voluntariness is generally simply deduced from the commission of  the act: if I stabbed someone it is a reasonable inference that I did so voluntarily (note that saying so does not presume what mens rea I had, whether I had foresight of the consequences, etc). To invoke a defence of automatism, you must be able to argue that the automatism was unconscious: you cannot "see yourself" in a situation of automatism. Successful invocations of non-mental disorder automatism are rare but not unheard of, as seen in the case of Parks. Such cases may be controversial where there is doubt about whether the automatism in question is mental disorder related or not (as was the case in the Joudrie case for example). If it is related to a mental disorder, we saw that specific "not guilty by reason of mental disorder" consequences follow; it is not neurological or psychiatric, then a full acquittal is the only possible outcome. In the Parks case, one sees the absolute limit of the criminal law: this was just a very unfortunate (and extremely rare) event about which the state cannot do anything within Charter principles (you could always lock up anyone who sleep walks lest they commit a crime in the process, but needless to say that would not go anywhere constitutionally).

Duress and necessity

But can automatism arise not from some physiological or psychological event but from some external circumstance? How crushing would such a circumstance have to be to negate voluntariness altogether? Duress and necessity raise a different set of issues and don't operate in quite the same way as a non-mental disorder defence. They are considered "excuses" that negate the element of "normative voluntariness" of the offence.

The statutory defence of duress ("compulsion by threats") is contained in section 17 of the Criminal Code and we will focus on that rather than the residual common law defence of duress. That defence comes with significant exclusions in the case of "high treason or treason, murder, piracy, attempted murder, sexual assault, sexual assault with a weapon, threats to a third party or causing bodily harm, aggravated sexual assault, forcible abduction, hostage taking, robbery, assault with a weapon or causing bodily harm, aggravated assault, unlawfully causing bodily harm, arson or an offence under sections 280 to 283 (abduction and detention of young persons)." There must otherwise be threats of death or bodily harm to a third party (otherwise self defence would be involved) and the accused must "believe that the threats will be carried out". The requirement that the treat be immediate was found unconstitutional by the Supreme Court in Ruzic, although there must still be close temporal connection, otherwise it will become difficult to explain why you did not seek help and alert the police to the compulsion. Moreover the defence does not apply to persons who are parties to a conspiracy or association that is the cause of the compulsion (too bad for you if you joined a conspiracy). Finally, to these statutory requirements must be added common law requirements such as the absence of a safe avenue for escape and, most crucially, proportionality. 

The defence of necessity in Canada is still determined by the common law. The difference with duress is that the compulsion is created by events, not a third party. Imagine for example that you are lost in the woods in the middle of the Canadian Winter and will probably die if you do not break into a chalet. The criminal law has a certain understanding for the fact that in situations of emergency one may engage in behaviour that would otherwise be illegal. Necessity is sometimes described as "duress of circumstances." The Perka case provides a good illustration. You must show that you were in imminent peril or danger (not just a foreseeable or likely one), had no reasonable alternative, and that the harm you inflicted was proportional to the harm avoided. The test is a modified objective standard that takes into account the situation and the characteristics of the accused.


The question of intoxication is particularly sensitive given the involvement of alcohol and drugs in the commission of many offences. This is a tricky situation for the criminal law. On the one hand, someone who is intoxicated may indeed not have or be incapable of forming the right mens rea, or be in a position to invoke a mistake of fact where knowledge is an element of the actus reus. On the other  hand, society has a strong interest in protecting itself and victims from alcohol induced crime. The resulting position in Canadian criminal law is one that is quite wary of allowing alcohol to be invoked as a defence. Your diminished ability is not a defence. You might say that just as having been drunk is not a defence when driving, being drunk is not a defence to committing a range of criminal offences. Moreover, drinking to give yourself "the courage" to commit a crime is certainly not a defence. It is also clear that for objective mens rea offences, being drunk is not a defence: the reasonable person in Canadian society is not supposed to be drunk to the point where she cannot behave like a reasonable person.

But the rule could be too harsh. For example, you might be intoxicated despite yourself, for example as a result of a drug that was given to you without your knowledge (involuntary intoxication). Paradoxically, the Supreme Court once had more understanding for extreme intoxication than ordinary intoxication. In the latter case, although you may be emboldened by alcohol, you are clearly capable of forming a certain mens rea, and a fortiori of engaging in voluntary acts. But what of a person who is so drunk that they are reduced to an automaton, that they are virtually unconscious? The Supreme Court found in the Daviault case that, based on the Charter, defendants ought to be able to introduce a defence of extreme intoxication automatism on a balance of probabilities even in the case of general intent offences (despite its earlier pre-Charter ruling in Leary) and therefore a fortiori still in specific intent offences.

Parliament reacted to this by adopting section 33 of the Criminal Code which now clarifies that you cannot invoke a defence of intoxication (not even extreme intoxication) if you "depart markedly from the standard of reasonable care generally recognized in Canadian society". That standard of care is expressly codified as being that you, through your own self-induced intoxication, have "rendered (yourself) unaware of, or incapable of consciously controlling, (your) behaviour, (and you) voluntarily or involuntarily interfere or threaten to interfere with the bodily integrity of another person." Obviously that probably covers most cases of intoxication. Note also that it substitutes an objective mens rea standard to proof of a subjective one.

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