One of the things I noticed yesterday while driving in the snow was that some folks didn't have their lights on. This topic tends to come up frequently in community Facebook groups whenever people drive in rain or snow. Truth is, driving in rain or snow, when visibility can be limited, without lights isn't just a poor choice. It's also illegal.

Why People Might Choose To Drive Without Lights In Missouri

Some of this is probably due to the fact that many cars at this point have automatic lights. Between daytime running lamps and automatic sensors that turn your lights on and off, we do not have to remember to do that when driving around sunset or even when we're driving at night. The car turns the lights on and turns the lights off.

However, The problem arises when we may get snow or rain, yet it doesn't get dark enough to turn your lights on automatically. That seemed to be the case with the February 18, 2025 snowstorm. It was light enough not to trigger some vehicles' light sensors, but visibility had decreased enough that seeing tail lights helped a lot. I manually turned my lights on to ensure others could see my vehicle.

Other reasons people might have chosen to drive without their lights are that they forget to turn them on, feel they don't need them or are ignorant of Missouri's windshield wiper law requiring lights to be on when windshield wipers are being used.

What Missouri Says About Lights and Windshield Wipers

Missouri State Statutes require the use of your headlights when you are using your windshield wipers. Here's what the law says specifically:

"When lighted lamps are required means at any time from a half-hour after sunset to a half-hour before sunrise and at any other time when there is not sufficient light to render clearly discernible persons and vehicles on the highway at a distance of five hundred feet ahead. Lighted lamps shall also be required any time the weather conditions require usage of the motor vehicle's windshield wipers to operate the vehicle in a careful and prudent manner as defined in section 304.012.  The provisions of this section shall be interpreted to require lighted lamps during periods of fog even if usage of the windshield wipers is not necessary to operate the vehicle in a careful and prudent manner."

Aside from the specific nature of the law requiring lights when running your windshield wipers, if you relate this statute to section 304.012, which requires Missouri drivers to exercise the highest degree of care while driving, and the specifics of the law that say lights are required in foggy conditions even if you're not using your car's wipers, I'd suggest, that a police officer could give you a ticket for not having your lights on in conditions that warrant being more visible regardless of whether or not you're using your wipers.

Bottom Line

As a Missouri driver, you're supposed to exercise the highest degree of care while driving. Sometimes, depending on the car you drive, that may mean manually turning your lights on based on weather conditions, regardless of whether or not you're using your windshield wipers.