What color can brake lights legally be?

Brake lights legally must be red or amber to comply with traffic safety regulations. The primary function of brake lights is to alert drivers behind a vehicle that it is slowing down or stopping, thus enhancing road safety. The red color is most commonly recognized for this purpose, as it conveys the idea of caution and signals drivers to be prepared to stop. Amber can also be utilized as an additional cautionary signal, although it is less common for brake lights.

Using colors like blue, white, or green for brake lights does not conform to standard vehicle safety regulations and can lead to confusion on the road, potentially increasing the risk of accidents. Therefore, the legal requirement for brake light colors to be red or amber is crucial for maintaining clear communication among drivers in traffic.