It absolutely does not work. Violence finds a way.

The mind is humanity's most lethal weapon. With the "right" mindset the entire universe can become a weapon. Efforts to reduce violence tend to focus on the presence of concrete weapons (because this is easier to quantify and measure etc) with much less focus on violent ideation and the root causes of the various forms of interpersonal violence.

Reducing violence is a tricky thing because to a large extent it seems to me to be a symptom of broader and nearly intractable societal malaise. Not that it isn't worth removing nuclear weapons from circulation but the returns diminish quicker than most public policy folks seem to want to admit.

Also ever since “driving while black/poor/not liked” became something you couldn’t arrest on they need another excuse.

I don't know enough about when various laws were passed to say whether the introduction of the laws have had an impact. In 2021 the Office for National Statistics published a reasarch breifing on the topic with some top level numbers [1]. I can say I don't walk around expecting people to have a weapon on them, even in some of the higher crime areas of my city (Bristol). But that's just anecdotal and it'll greatly depend on where you live.

[1] https://commonslibrary.parliament.uk/research-briefings/sn04...

Speaking for myself, I own a Buck Hunter knife that I used to carry as a pocket knife. When I learned that it's not street-legal (it's blade locks, and is 1/2" too long) I stopped carrying it. So that's one anecdatum. I'm not particularly unusual; I imagine many people that once carried a locking pocket knife no longer do.

There was a spate of stabbing reports, about a decade ago. That seems to have died down. My guess (and it's only a guess) is that only drug dealers and people bent on mayhem carry guns or knives that aren't street-legal these days; what's the point in getting busted for carrying a penknife?

Incidentally, I don't get the point of the ban on locking knives. If you stab someone with a knife that doesn't lock, then I suppose there's a risk to your own fingers; but the dude you stabbed won't care if it was a locking knife or not. I do get the blade-length restriction though. You don't need a 3" blade to sharpen pencils.

My straight razors are street-legal, though, and I think they're quite a lot more dangerous than a 3" knife that locks. The sharpened edge of a razor is only about 2" long, so I assume it's street-legal; but you could really make a mess of someone's face with a razor (the preferred weapon of Pinky, the gangster from Brighton Rock).

Another piece of anecdatum: a vague friend of mine once had a routine traffic stop by the police as he'd renewed his car insurance on the day it expired and the change hadn't made it onto the database they use yet. The police officer asked something like "just as a routine question, do you have anything on you that you might think you shouldn't have, like knives etc". He was (at the time) a professional chef and had a large roll of huge, high end kitchen knives on the back seat of the car. He also had chef's whites and was driving to work. The policeman said that apparently a few smarter drug dealers had started doing that (keeping them in a roll) as it was more plausible that they'd be cooking with them rather than stabbing their mates. The give away, apparently, was that they'd just have one massive one and not bother with the chef's job and still end up with a few years in prison.

My friend "got" a nice chat, and went on with his day, but did later comment that had he not had the outfit to go with them, and a vast array of obvious kitchen tools, he thought that they'd probably look at it a lot more seriously.