Doesn't lock, try using a swiss army knife against somebody and you will probably end up hurting yourself more than them. Unless the person is doing something very dodgy, your average swiss army knife would be ignored. I can't carry my leatherman in the car anymore though unfortunately since I saw on TV somebody being arrested for it, previously I carried it as part of the tool kit.
It's not worth the risk, especially since if I am in a position to use/have a knife used against me, I will have made far too many mistakes already.
A friend of a friend used to carry a baseball bat he referred to as "Justin" - when asked why, it was "Just-in-case" lol.