Rules of the Road

Do you have to turn on your headlights in the rain? Here’s what the law has to say

Laws require that headlights be used from a half hour after dusk until a half hour before dawn and at any other time when or conditions make it difficult to see.
Laws require that headlights be used from a half hour after dusk until a half hour before dawn and at any other time when or conditions make it difficult to see.

Question: I am concerned about the significant number of drivers I see on our roads that do not turn on their headlights at dusk or when visibility is poor during the daylight hours. Many drivers seem to refuse to turn on their headlights when there is fog, drizzle or other poor lighting. I'm sure they think that they can see just fine, but often I don't see them until they have gone by in the oncoming lane. It seems to me that if drivers had their headlights on at all times (night and day) we might have fewer accidents during poor visibility conditions. What is the law on this?

Answer: I’ll get to the law, but I’d like to start by responding to the comment that “many drivers seem to refuse to turn on their headlights . . .” Maybe there are some drivers who think to themselves, “Wow, it’s pretty rainy out. I should turn on my headlights, but that would take too much effort. I’ll just leave them off.” However, I suspect that most drivers don’t think to turn on their headlights to begin with. I also have a suspicion as to why.

We think of headlights as a tool to help us see, which makes sense, since that is why they were put on our cars in the first place. But a secondary role, which is actually quite important, is allowing other road users to see us. If we’re not conditioned to think about being seen, as long as we can see where we’re going, we won’t think to turn on our lights.

The earliest version of the law requiring drivers to use headlights that I could find dates back to 1927. Interestingly, the language is nearly identical to our current law, with one notable difference, which I’ll get to in a moment.

Both the old law and the new require that headlights be used from a half hour after dusk until a half hour before dawn, and at any other time when, due to insufficient light or weather conditions, pedestrians and other motorists are not clearly discernible.

Here’s the difference: the old law only required visibility for 200 feet; the current law requires 1,000 feet. You might say that’s a safety improvement, but you also have to consider the speed limits. In 1927 the maximum speed limit in the state was 40 mph, the maximum in city limits was 25 mph, and in many areas it was limited to 15 mph. The distance requirements increased along with the speed limits. (Fun traffic trivia: In 1909 the top speed limit in the state was 24 mph and some limits were as low as 4 mph.)

Notice that the focus of the law is on being able to see other things; there is no requirement to turn on your headlights to be seen. You might argue that it’s semantics, because if you can’t see other cars, they can’t see you either, so you’re both required to turn on your headlights. I won’t disagree. I’ll just point out that the language of the law doesn’t give attention to being seen.

That same mentality creeps into our driver training and our driving habits. The Washington Driver Guide places an emphasis on using headlights primarily as a tool to see, although I’ll also give it credit in that later in the chapter on safe driving tips it does recognize the benefit of using headlights to be seen.

If you ask most drivers they’d probably tell you the same thing Google told me; that the “purpose of headlights is to illuminate the road.” The focus is on seeing rather than being seen.

Studies show that using headlights in the daytime reduces multi-vehicle crashes. Essentially, every car is equipped with an additional safety feature at no additional cost. We don’t have to wait until a law is written to turn on our headlights during the day. There’s nothing that prohibits it. All we have to do is reach out with one hand and turn a knob.

I know that for the people who don’t use turn signals it sounds really difficult, but for the rest of us, it’s just developing a new habit. I’ll admit that I’m not perfect at it, but I’m working on the habit myself.

In many countries this problem has already been solved. Car manufacturers are required to equip new vehicles with daytime running lights (DRL). In the U.S. it’s an option, but not a requirement. Until we all have cars equipped with DRL, let’s make an effort to be seen by turning on our headlights. It’s a simple way to increase safety as we drive.

Road Rules is a regular column on road laws, safe driving habits and general police practices. Doug Dahl is the Target Zero Manager for the Whatcom County Traffic Safety Task Force. Target Zero is Washington’s vision to reduce traffic fatalities and serious injuries to zero by 2030. For more traffic safety information visit Ask a question.