I fell on this looking up the legality of conceiled knives under Canadian law. I think the reasoning might help see how a judge could consider both the social impacts of weapon carrying and the right of a person to defend themselves. So I'll post it.
"The usual internet explanation of Canadian knife laws leaves out the fact that in 2011, the judicial understanding of the offense carrying a concealed weapon changed in a very important way.
There are three basic ways that the existence of a weapon is established for the offense, and the one most likely to catch a good-natured but unaware person involves the following consideration: are you carrying [a knife] designed to be used to cause death or injury or for the purpose of threatening or intimidating anyone. It is the application of this part of the offense that changed.
The case can be found here. Anyone contemplating carrying a knife in public in the way described above should read it.
For those who want a quick summary: In determining whether something fits into the above-noted definition of a weapon, the Court must now only undertake an objective analysis by asking itself:
Is the object's design such that it could be readily usable to cause death or injury to any person or to threaten or intimidate any person?
In all of the circumstances, would the carrying of the concealed object cause the reasonable person to fear for his own safety or for the public safety, if he were aware of the presence of the object?
In the case I linked to, the knife was described as follows:
The steel knife is approximately twelve inches in length; its blade is approximately seven inches long. On the blade are the words "U.S.A. SABER." The lower part of the blade is sharply honed. Part of the top part of the knife is serrated and other part has five ridges. This is clearly a combat knife and not a simple hunting knife.
The accused was convicted.
Consider what a karambit is, what it looks like, how it's marketed, and what conclusions a fifty or sixty year old Judge would come to when considering the above two questions.
In considering the above, the court made the following comment which may be helpful:
It is recognized that the second half of this bipartite test [question 2] is contextual and that, in deciding this question, the court is called upon to conduct a holistic analysis. That may be difficult, but it seems to me that it is what is required in order to give effect to Parliament's intention. In conducting this analysis, the court must be ever mindful of Parliament's purpose in enacting this section, that is, firstly, minimizing the furtive carrying of objects that pose a real threat to public safety, and secondly, that would cause justifiable alarm in members of the public contributing to general paranoia.
Such an analysis will take place against the backdrop of the object being both carried and concealed, as both of these factors are elements of the offence. It will require the court to look at the characteristics of the object itself. It seems to me that the reasonable person would consider the carrying of a jackknife in a pocket (the typical way of transporting a jackknife) to be innocuous. Similarly, a butter knife would be viewed as non-threatening. A large skinning knife would be more worrisome. In my view, the definition would capture virtually all prohibited weapons. Other factors will also be relevant, including the locale where the object is being carried. The reasonable person would surely be more concerned where the object is imported into a public venue such as a bar than if the object is carried by a person engaged in a solitary activity.*" "
Lifted from
https://www.reddit.com/r/knives/comments/3kskpk/karambit_knife_illegal_or_legal_in_canada/