Here’s another point that I found interesting in the Supreme Court’s decision in R. v. Tatton, 2015 SCC 33. (I wrote about Justice Moldaver’s comment regarding mandatory minimum sentences yesterday.) The issue in Tatton was whether self-induced intoxication could be invoked as a defence to a charge of arson ― but Justice Moldaver, writing for the unanimous Court, also sought to clarify the broader question of the sorts of offences to which intoxication can be a defence. The distinction between offences for which this defence is available and those for which it is not “continues to perplex counsel and trial courts alike,”  says Justice Moldaver. And, worse, this
confusion … is part of a larger problem that has plagued the Canadian criminal law for decades. Regrettably, the Criminal Code often provides no clear direction about the required mental element for a given offence. It is therefore left to judges to attempt to divine the required mental element (also referred to as the degree of fault). 
Justice Moldaver notes that “academics and law reform bodies have urged that the Code be amended to specify the mental element and fault requirement for each crime”  and adds his own voice to the chorus:
Legislative intervention is sorely needed to spell out the mental element of offences and to specify when intoxication short of automatism can be considered. 
This call for help tells us something interesting about the respective roles of courts and legislatures (Parliament, in this case) in developing the law. Justice Moldaver does not appeal to Parliament because courts cannot themselves work out the mental element of an offence or whether it is such that intoxication should be a possible defence. After all, the Supreme Court does just that in Tatton ― seemingly, without too much trouble, at least if the decision’s concision and unanimity are any indication.
The reason why “legislative intervention is sorely needed” is that judicial decisions work things out piecemeal, which creates a twin Rule of Law problem. First, decisions can be inconsistent, with apparently similar offences treated differently, and indeed courts disagreeing among themselves regarding the treatment of any one offence, at least until the Supreme Court clarifies matters. It is perhaps worth noting that in a perfect Dworkinian world, where judges excel at “fitting” their decisions with all the others so that the law is the proverbial seamless web, this problem should not arise. But the perfect Dworkinian world is not the one in which we live.
Second, partly as a result of these inconsistencies, the litigants have a hard time knowing what the law even is. Now, while a person’s being subject to criminal liability for infringing a law of which he or she could not be aware is widely regarded as perhaps the worst possible Rule of Law infringement, the obscurity of the law regarding mental states generally and especially intoxication might not be quite so bad. People should refrain from getting drunk and doing stupid and dangerous things, regardless of whether they can be prosecuted for doing them. Even if Mr. Tatton, who set the house where he lived on fire ― not out of malice, it seems, but as a consequence of being in a state that a certain ex-mayor would have described as a drunken stupor ― could have invoked this state as a defence to a criminal charge, his actions would still have been unambiguously wrong, and even he surely would not have disputed that. Still, not every action that is morally wrong is criminal, and so there is a moral loss in prosecuting people on the basis of an unknowable law, even for independently reprehensible conduct.
By clarifying things across the board and at once, legislation can solve Rule of Law problems caused by the slow and sometimes disorderly development of the law by the courts. But then again, real-world legislation doesn’t always do that. Later on in his opinion, Justice Moldaver mentions sexual assault as an example of offence for which the defence of intoxication is not available. In a footnote, the only one of the opinion, he adds:
The Criminal Code now explicitly states that an accused may not rely on intoxication to support his mistaken belief in the complainant’s consent: see s. 273.2. However, this was the position at common law long before s. 273.2 was enacted.
Perhaps I’m overthinking this, but I cannot quite shake the impression that Justice Moldaver is being somewhat snarky, if not a bit passive-aggressive here, and telling Parliament something like “we really didn’t need you to tell us that.” But that would be at odds with his earlier call for legislative intervention, wouldn’t it?
Not necessarily. A single provision like s. 273.2, which applies to a very narrow set of offences, is precisely the sort of piecemeal clarification that courts themselves are perfectly capable of supplying. It contributes nothing to a more “big-picture” view of the law of mental states or intoxication. Parliament might have had its reasons for enacting it (symbolic reasons, perhaps), but Justice Moldaver may well think, and would have a reason for thinking, that its energies would have been better spent elsewhere ― namely, on the more difficult business of the sort of law reform that Parliament is uniquely well-positioned to enact. Parliament should help the courts, but it should go about it the right way.