In my area I can get pulled over for exceeding the speed limit, or the more nebulous "impeding the flow of traffic" aka driving too slow. On average, most drivers speed on the highways here, so it ends up being illegal to go with the flow and illegal to not go with the flow.

My favourite has been "exceeding the speed limit"

Which is fine, EXCEPT that it wasn't the *posted* speed limit, it was the *gazetted* speed limit (that is, the signs were incorrect and driving to them was illegal