What is "Reasonable" Under Canadian Law?

All the usual caveats:none of you are my lawyers, I am not asking for nor are you proffering advice, you are providing information on a general question, should I have a specific _______ I should talk to my lawyer which none of you, most assuredly, are :slight_smile:

“Reasonable” seems to show up in lots of contracts, civil suits, criminal cases and I’m sure many other areas.

I’ve done some internet reading and I’ve gleaned that the standard seems to be what an ordinary person would consider to be fair/understandable/likely/ given the facts as known and the circumstances.

That seems pretty much as murky to me as “reasonable” does.

So what is the functional definition of “reasonable” under Canadian Law? Pick provinces, federal and any area of law you like. It seems an important concept given its apparent ubiquity so I’d like to get a feel for it.

Thanks :slight_smile:

Well, in the criminal law context, here’s how the Supreme Court of Canada has defined it, in R. v. Lifchus:

Nowhere in that quote is “reasonable doubt” actually defined.

Reasonableness is pretty much the essence of common law jurisprudence.

It’s undefinable precisely because it is defined on a case-by-case basis and that’s how justice is best dispensed (according to our system): getting a bunch of non-interested members of society to decide which side’s statement of the dispute is more reasonable than the other’s

Does the ‘man on the Clapham omnibus’ have a local Canadian equivalent?


Law is not algebra. Concepts are not always well-defined, even important ones. “Fairness” is an issue that crops up constantly in criminal matters, and it too is poorly defined, if at all. The concept of reasonableness also pops up in issues such as reasonable necessity in self defence and in lots of other places. And the application of the concept to whether a prosecution case is proved, to whether a killing is justified by self-defence, and to whether a “reasonable man” would have mopped a spill off the floor so preventing an injury demonstrates that “reasonableness” is applied so widely that no over-arching definition which applies to all such situations yet is as precise as a proposition from Euclid can ever exist.

This is why threads which ask “If someone is coming through my front door in the dark of night, is it OK if I shoot him?” can’t be answered definitively as though someone were asking what is the length of the hypotenuse of some particular triangle. To judge reasonableness, you have to use your own common sense compass.

The law values a priori “knowability” of whether a person can determine if they are about to commit an offence in a theoretical sense, but not to the end of reckoning, or in truth, very far at all. The idea that a person should be able to know in advance of an action whether they are breaking the law tends to arise most in matters of the creation of statutory offences - it should in principle be possible for a person to know in advance whether arranging their affairs in some particular way will fall foul of the tax laws, for example. But individual facts of different cases in the general area of criminal and other branches of the law are too variable to give advisory answers up front, or definitions of of vague concepts, because there is no way to avoid one small fact changing everything.

Thus, the general answer to the question I posed above about a home invader might be yes in some particular jurisdiction, but that might change if the person coming through the door was unarmed and in a wheelchair, and to the knowledge of the shooter a family member of the household was known to be confined to a wheelchair.

This is why we get a dozen people to thrash this stuff out. The reasonableness of many if not most things can only be judged after the event.

I remember many years ago when the Rolling Stones were performing in Toronto, Keith Richards had his hotel room searched and they found “drugs” what a surprise. But he challenged it in the courts that it was an “unreasonable” search?
As I remember the court ruled that even though it was illegal (the search) the finding of the drugs was more important and he would still/could be charged.

It ended up he agreed to hold a free concert in Oshawa just east of Toronto and held only about 8000 people.

Then there’s the “Gordon Lightfoot” DUI defense… Just because you were over the limit when you reached the police station and blew into the breathalyzer, does not mean that you were necessarily over the limit a while earlier when the police pulled him over. The judge thought that was a reasonable doubt. Oddly enough, the appeals court didn’t.

Another explanation is “what would the average person do in that situation”? It’s reasonable force to pull a gun and shoot if the guy racing towards you is a foot taller and swining a baseball bat. It’s not reasonable if they are much shorter and lighter, and using their fists… etc.

As for Keith - it’s not reasonable to say “those rock stars are all dopers, so that should be enough grounds to search their room”. To do a valid search, the reason/grounds for the warrant must meet the same proof as for anyone else. Unlike the USA, evidence does not automatically get tossed if it was improperly obtained. It’s tossed if its use would “bring the administration of justice into disrepute”, anothe weasel lawyer phrase with plenty of wiggle room. Torture - bad for justice. Lying to the judge who issued the warrant - maybe. Being mistaken about grounds for the warrant? Probably not- better have a good lawyer…