i like to think that for the sake of corner crossing, in that moment of time, that pin is basically divine fact regardless of it's correctness. i couldn't imagine you could charge someone based on the idea that the pin was off.
i suspect property disputes are a whole different can of worms. but, even so, wouldn't you think that until the property dispute is settled the current state of correctness of say, in this case a pin, remains as is until decided otherwise?
but hell if i know, i'm just some guy