Originally Posted By: TheSock
Well since you asked OBG :-)
If I may add to that...

Quote:
A knife with a blade more than 3 inches in length is illegal. A knife with a locking blade is illegal.
That is, illegal to carry in public without a good reason. They are legal to own and use at home, and they are legal in public if, eg, you need it for your job, or if you just bought it and are carrying it home, or if you are travelling to or from the airport. This is mostly common sense and honesty.

(A locked car boot is technically not a private place, but no-one is likely to look in it anyway.)

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If you admit to the police 'yes i suppose i would use my leatherman (or paper, or umbrella or anything) you just admitted to a crime.
I think you missed out the words "self defence". Carrying a blade for self-defence is a crime. Self-defence is not a "good reason". This may be a surprising point for Americans.

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But we have had a few cases of people being arrested with leathermans and being found innocent in court.
Basically you have to convince the court it's carried as a tool, not a weapon.

Be aware that the owner of a particular establishment may impose their own rules, which may be stricter than the law. For example, The London Eye has a reputation for taking even legal blades off customers before they go on the ride. (The ride involves being sealed in a bubble with other customers high above the ground, and I guess they are terrified of a knife-fight breaking out in such circumstances.)

Apart from places like that, you are unlikely to get searched. Police need "reasonable suspicion" to search you. However, if you get arrested for something else, they'll probably take sharps (and cell phone) off you then.
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