"they would put two blades in and separate them so that the resulting cut could not be sutured, leaving an almighty scar."
Ouch.
In the UK, Italy, etc., is it legal to carry a pocket knife?
In Texas, the overall length of the knife has to be under or no more than 9 inches. I'm not sure it matters whether it's a folder or not. I don't think a dagger is legal to carry (double-sided blade). I've never seen anyone with a large hunting knife sheath on their belt, just those carrying a large folder. Automatic knives are legal to own but not to carry unless you work as a EMT or law enforcement.