Are you saying that everyone easily agrees on what a “vehicle” is, except in the case of a police car or an ambulance? That roller skates are clearly either a

Are you saying that everyone easily agrees on what a “vehicle” is, except in the case of a police car or an ambulance? That roller skates are clearly either a vehicle or not, but a police car is a gray area? note that the question was whether the rule “no vehicles in the park” has been violated, not whether it should be allowed to be violated.