Yes, it is generally legal to drive with your interior car light on, but it is strongly discouraged as it creates a significant safety hazard. The primary risk is reduced visibility. The glow from inside the cabin reflects off the windshield and windows, acting like a mirror and severely limiting your ability to see pedestrians, animals, and obstacles on dark roads. This effect, known as compromised night vision, occurs because your eyes adjust to the brighter interior light, making it harder to perceive the darker environment outside.
While no state has a specific law that outright bans driving with an interior light on, you could be pulled over for impeding traffic or reckless driving if the light causes you to drive erratically. The danger is most acute on unlit rural highways. If you need to use the light, such as to find a dropped item, the safest practice is to pull over to a secure location first.
Modern vehicle design often includes dimming features for dashboard and interior lights to minimize this issue. However, a bright dome light, especially one turned on manually, overrides these systems. The core advice from safety organizations like the National Highway Traffic Safety Administration (NHTSA) is to keep the cabin dark while driving at night to maintain optimal external visibility.
| Jurisdiction | Specific Law Against Interior Light? | Potential Citation Under | Key Safety Consideration |
|---|
| California | No | Reckless Driving (VC 23103) | Glare on windshield reduces peripheral vision. |
| Texas | No | Impeding Traffic (Tex. Trans. Code 545.363) | Compromises depth perception on dark roads. |
| New York | No | Careless Driving (VAT 1212) | Creates a distraction for both driver and other motorists. |
| Florida | No | Driving in Unsafe Manner (FS 316.183) | Increases reaction time to unexpected hazards. |
| Federal Guideline | N/A | NHTSA Safety Recommendation | Interior lights can reduce night vision by over 50%. |
