Is it illegal to carry a knife around in my pocket?
It's illegal to carry any sharp or bladed instrument in a public
place, with the exception of a folding pocket knife which has a
blade less than 7.62 cm (3 inches) long.
A lock knife is not a folding pocket knife and therefore it's
illegal to carry around regardless of the length of the blade.
A lock knife means a knife which is similar to a folding knife,
in that there is a spring holding the blade closed. However, a lock
knife has a mechanism which locks the blade in position when fully
extended and the blade cannot be closed without that mechanism
being released. A lock knife is not automatically an offensive
weapon because these knives were made with a specific purpose in
mind and not as a weapon. However, possession of a lock knife in a
public place without reasonable excuse is an offence.
Possession of a multi-tool incorporating a prohibited blade or
pointed article is capable of being an offence under this section
even if there are other tools on the instrument which may be of use
to a person in a public place.
The ban is not total, but it's for the person in possession of
such an instrument to prove on the balance of probabilities that he
or she had good reason for its possession. For example, someone
backpacking across the Lake District may reasonably be expected to
have a knife for the preparation of meals. It will be far more
difficult to justify on the streets of a city or town, but there
will be occasions when someone is genuinely going to something like
a martial arts class or scout meeting.
The penalty for committing this offence is a maximum prison
sentence of four years.