Comment by ben_w

For me, it is obvious that police and ambulances in emergencies violate the rule.

They may have some higher-level rule that says "in emergencies we don't get punished for violating this category of rule", but the rule is still there, and requires the drivers to demonstrate that there was in fact an emergency.

A hierarchy of rules is why normal people don't get to act like cops, or perform amateur heart transplants.

Bikes are a more interesting edge case for me; I think they are, as I expect the reason for the rule to be some kind of environment degradation, possibly easily damaged lawns or similar. But they might be fine. Depends on the reason for the rule.