My mate who is a farmer went into the court to pay a fixed penalty speeding fine. He emptied his pockets before going through the metal detector and in his belonging was his small penknife for cutting bailing twine.
He got a night in the cells and took to court in the morning. Luckily enough he only got a caution.
I'm a bit sceptical about this one I'm afraid. There is no law against carrying a folding penknife with a blade less than 7.62cm (3") anywhere. If the blade was a locking blade then I could understand why your farmer friend was arrested. Also, unless there was far, far more to the story than you have related, no one goes straight to court from police cells without some pretty heavy exceptional circumstances. If it was a folding pocket knife, his arrest was unlawful. If he really spent a night in the cells, then it wasn't a folding pocket knife.
Here's the Gov.UK guidelines :
The laws on selling, buying and carrying a knife or weapon depend on the type of knife or weapon, your age and your circumstances.
www.gov.uk
To answer the original question, there are two specific pieces of legislation which can apply to knives.
Section 1 of the Prevention of Crime Act 1953
makes it an offence to have an offensive weapon in a public place without lawful authority or reasonable excuse.
Here, an offensive weapon is any article made, or adapted, or intended by the person having it with him, or by another, to cause personal injury to any person. So it would include knuckledusters(made to cause injury) a piece of wood with nails driven through it (adapted to cause injury) or a rounders bat (an innocent piece of sporting equipment, carried to a fight intended to cause injury) There are certain types of knives and weapons which are included in various schedules and are defined as "offensive weapons per se" such as balisong knives, switchblades, knuckledusters, coshes, etc.
Public place is any place where the public has access, on payment or otherwise, so the street, or a stadium/nightclub etc.
The offence is complete if the person having it with him intends to use the item to cause injury by him or by another person. In other words you can't carry a weapon for a mate to use.
By definition, if you carry a small "legal carry" penknife
with the intention of using to to cause injury the offence is complete, but it is only defined as an offensive weapon by way of that
intent
Lawful authority means some people can carry what would otherwise be offensive weapons, eg a copper's baton, and reasonable excuse would be a theatre prop, or Mrs Miggins taking the cosh she's confiscated off little Johnny to the police station to hand it in.
Section 139 of the Criminal Justice Act 1988 makes an offence of having an article with blade or sharp point in a public place without lawful authority or good reason. Section 139A of the Criminal Justice Act 1988 provides that it an offence to have an article within either of the above offences on school premises. Sections 139 and 139A of the Criminal Justice Act 1988 apply to any article which has a blade or point except a folding pocketknife unless the cutting edge of its blade exceeds 7.62 centimetres (3 inches).
Here the act is pretty simple. You mustn't have with you in a public place (again, street, nightclub, stadium, cinema etc) any item which has a bladed edge or a sharp point. So that includes any knives, or swords, or machetes, or darts, or school compasses, or (....you get the picture) unless you have a reason to do so. This time it's up to you to convince the court that you had a good reason. So a carpet fitter on their way to work can carry a stanley knife, but not when they go to the pub. A Darts player can take their sharply pointed items to the pub, but not to the football. A chef can take his or her 32 piece professional Japanese knife set to work, but not to Butlins at the weekend.
The only exception is the good old folding (not locking, not fixed) pocket knife as long as the cutting edge of its blade doesn't exceed 7.62 cm or 3". You don't need any foreseeable good reason to carry one of those.
Section 139A of the 1988 Act simply adds School premises to the list of places where the above 2 offences can be committed. The reason being is that the general public are not allowed access to schools whether on payment or otherwise, so it closes a potential loophole or two. It also adds "for educational purposes" as a defence/reasonable excuse where applicable.
Otherwise, any premises may have their own rules for allowing or not allowing "legal carry " knives. It's their premises, their rules, but no specific legislation exists other than the above.
