For example the rule of what side of the road to drive. Pour conscience probably tells you nothing about it, but your ideas may suggest that some places other side is better.
Also, there could be stuff you simply don't understand, but the law is easy to follow. Speed limit may look way too low, but there is a hidden problem in the area for example.
Other situations have graytones, where you are not a hundred percent in agreement with an order, but you do understand some of its merits.
