That all seems a bit excessive doesn't it? Does that mean you can't carry a pocket knife either? I would be lost without my Leatherman or at least a swiss army knife.
As for knives in the UK: so long as the blades under 3 inches long, and it is a non locking folding knife, it is legal to carry in public (with some exceptions).
Any knife longer than 3 inches, or any knife with a locking blade, cannot be carried unless you have a good reason (eg: going to/from work, etc).
You likely will have to argue this reason in court if the police officer is a cunt, and most of them are cunts when it comes to having common sense around blades.
Fixed blade knifes of any length require a "good reason" to carry.
A lot of coppers in the UK are ignorant as fuck too, and will confiscate your folding, non locking, sub-3 inch Swiss army knife requiring you to jump through burning hoops, wade through an ocean of piss, and sacrifice a virgin goat at midsummar to get it back.
At the other end of the spectrum my kid can walk around with a machete and be perfectly legal, but her school library can't have V for vendetta. Is there anywhere that doesn't nanny about access to ideas or "weapons" (I'd rather use an umbrella as a weapon than a Leatherman if it came to it).
In defence of the police officers, you are probably dealing with similar level of anxiety as soldiers. I imagine a high number of them have had to deal with a knife incident and just because you’ve got a taser, some training and some backup doesn’t necessarily mean it’s going to end well for you. There are quite a few reports of people (especially large blokes like rugby players) who can shrug off a taser and go on a rampage. It famously took 20 police officers to arrest Eddie Hall and that was before he became a professional strongman.
I’ve heard the expression “don’t go into a knife fight and expect to come out uncut”. As in, even if you win, there’s a high likelihood you’re going to have slash wounds on some part of your body somewhere. Yes a bit of common sense should be in order but I can also understand why they want to be very strict about these things. Having to deal with a knife fight and the aftermath probably isn’t a great day at work.
The problem is, if the officer doesn't believe your reason is good enough, you end up having to go to court over it - which is expensive, and you may well lose and catch a custodial sentence.
I can't really overstate how ridiculous the UK's laws around knives are.
Even tradesmen with glaringly obviously valid reasons to carry knives are recommended to lock them securely in a toolbox while not at the jobsite to avoid prosecution.
