Weapons and the law

Are you tempted to carry a weapon? Make sure you know all about knife laws, weapon laws and gun laws before you arm up.

a kitchen knife

In the kitchen: Legal. Out of the kitchen: A weapon

What is an offensive weapon?

An offensive weapon is any object that has been made or adapted to cause injury.

This covers:

  • Weapons built for the sole purpose of hurting people, like a knife or gun;
  • Something adapted to cause injury, like a sharpened snooker cue;
  • An object not designed to hurt anyone, but you’re carrying it round intending to cause injury, like nail scissors.

In defining what counts as a weapon, your intention (whether you meant to hurt someone) could be taken into account – depending on what you’re carrying.

If you’re caught with an offensive weapon

In the eyes of the law, it doesn’t matter if you were carrying a weapon around with you but weren’t planning to hurt anyone. If it’s obviously a weapon, you’re in trouble. And claiming you’re carrying it round for someone else isn’t an excuse either.

The only defence in law is “lawful authority or reasonable excuse”. It’s down to you to show that the weapon in question wasn’t made or adapted to cause injury.

If you’re arrested and found guilty of carrying an offensive weapon in public, you could get up to four years in prison.

And if, for any reason, that you hurt someone (grievous bodily harm), kill or almost kill someone, you could face life imprisonment.

Knives and the law in the UK

It’s illegal to carry any knife in public, even if you’re not behaving in a threatening manner and don’t plan to use it. You can face a penalty of four years’ imprisonment and a £5,000 fine for doing so.

It isn’t illegal in the UK to own a knife in private, like the bread knife in your kitchen. However, if any knife is used in a threatening way, in a private environment, like your house, it becomes an offensive weapon.

Under certain circumstances, it’s legal to be in possession of a knife in public:

  • If it’s a tool of the trade (i.e. you work in catering or carpentry);
  • For religious reasons (i.e. a Sikh kirpan);
  • If it’s a penknife (pocket or folding knife) less than three inches long (although it may be considered offensive if carried for the purpose of causing injury or harm).

What knives are illegal in the UK?

There are some knives which you cannot own under any circumstances, including:

  • Flick knives, also known as ‘switchblades’ – where the blade is hidden but shoots out when a button is pressed;
  • Butterfly knives – where the blade is hidden inside a handle that splits in two around it;
  • Disguised knives – where the blade is hidden inside something like a belt;
  • Sword-sticks;
  • Samurai swords.

Swiss Army knives are allowed, so long as the blade is under 7.62cm. However if any knife is used in a threatening way it becomes an offensive weapon.

Handing in a weapon

Police authorities regularly hold weapons amnesties where you’re free to hand in an offensive weapon without risk of prosecution.

Outside an amnesty, your circumstances dictate how the police would receive you. Whatever the reason you’re in possession of an offensive weapon, police advice is to contact your local station to make arrangements for handing it in.

If you’ve simply found a gun or a flick knife in public, police advice is not to touch it, but report the find by phone or in person at the local station.

Which other weapons are illegal?

You need to have a licence to own a gun and there are strict restrictions on getting one, such as proving you’ll only be using it to kill vermin, or that it’s an antique-type gun. You also have to get two people to tell the police that you’re responsible enough to own a gun.

These come under different laws from guns that use bullets. People under 18 aren’t allowed to buy guns or ammunition. If you are under 18 you can use an airgun at a registered gun club or if someone over the age of 21 is responsible for you.

Photo of kitchen knife by Shutterstock

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law| weapons


Updated on 29-Sep-2015