Short version, meet long version: This will mostly discuss US law. There fist major hurdle here is that most governments have a certification which lights on a road car must meet. If your lights don’t meet that- they’re illegal by default. The second hurdle is that most states and federal agencies have laws specifying:
- How many “auxiliary” lights a vehicle may have (this includes fog lights or additional day time lamps)
- The maximum number of forward facing lamps allowed on a car (hence why 4 headlamps is about the maximum one sees on any given car, and why auto makers done just put more lights to make consumers buy their cars out of a perception of safety.)
- Most entities specify for on road vehicles a height range which auxiliary lights must be between- usually a minimum and maximum distance from the road surface measured on level terrain.
It’s common in Europe and Japan to see “driving lights” which default to “on” with “parking” or headlights in the on position. Japan allows driving with only “parking lights” and not headlights in some situations where in the US this is illegal in essentially all situations. Older cars with “pop up” headlights often had reflectors or clear lenses in the bumpers where as overseas these lights had actually light elements. This is because with optional fog lamps these lights would exceed the legal parameters for forward facing auxiliary lights, and in the US are redundant because they cannot be ran without the headlights on as they can in other countries.
Similarly “fog light covers” like one often sees on trucks, aren’t just to protect the lenses of lamps- it’s a way for vehicles used off and in road to remain legal. By covering the lamps and making them inoperable from within the vehicle without manually removing the mechanical covers, those lights can usually be informally counted out of the vehicles external light count. Common sense of most officers or if issued a ticket, judges, will generally uphold that the light itself can’t be used on road with the covers in place and thus isn’t a light functionally for purposes of the law.
It’s also important to note that like many laws from lighting, window tint, mud flaps, oversized tires etc- the laws for many of these things aren’t fixed at a federal level but set for further regulation by states or even counties or cities. So even IF your vehicle adheres to all the laws where you live, if you drive it into another area which has different laws about what lighting is legal or what shade of tint is legal- you are subject to those laws and can get a ticket in the other jurisdiction according to their laws- not the laws of your home address or where the vehicle is registered.
Certain exemptions exist- California for instance has notoriously strict smog laws, however a vehicle visiting or newly brought to the state while registered in another is allowed to stay and operate within California for up several months a year providing its out of state tags are still good. This only applies to emissions though- all other laws for “road worthiness” including lighting must still be adhered to for a vehicle to be considered fit to drive on public roads. MOST police will USUALLY give a pass to visitors on a short stay for this sort of thing- but they aren’t required to do behave and be polite of dealing with an officer out of your home jurisdiction in hopes they’ll be reasonable.
Likewise- police in different areas may or may not have formal or informal policies to simply not care about certain laws being broken. Small town police in a rural mountain area are less likely in general to harass a local in a vehicle modified for off road capabilities in a way which is common but technically illegal if that person isn’t otherwise causing trouble such as tires extending past fenders- but are very likely to ticket you if you take the muffler off your diesel and drive through town at all hours.
@bethorien- lol. Yeah. That was the closer. In the end, it’s highly unlikely most police officers wouldn’t see that precariously positioned tower of lights with essentially no bracing and say: “what the hell are they thinking... no. No.” So beyond all the Miriam of other reasons and factors involved which one could be cited or stopped for- it is within the prerogative of a police office to stop and cite an individual just because they feel something is unsafe. “They might not know everything etc...” True. Which is why such a ticket will usually have a provision to send you to a state or other “referee” or inspector such as a brake and lamp inspector who will then either certify the vehicle safe or not. So regardless there will be fines and paperwork and headache.
- How many “auxiliary” lights a vehicle may have (this includes fog lights or additional day time lamps)
- The maximum number of forward facing lamps allowed on a car (hence why 4 headlamps is about the maximum one sees on any given car, and why auto makers done just put more lights to make consumers buy their cars out of a perception of safety.)
- Most entities specify for on road vehicles a height range which auxiliary lights must be between- usually a minimum and maximum distance from the road surface measured on level terrain.