What color of lights are prohibited from being visible from the front of a motor vehicle, except for police vehicles?

The correct answer is red because, in many jurisdictions, including those governed by traffic laws specific to the Dallas Police Department, red lights are traditionally reserved for emergency vehicles, particularly police cars. The visibility of red lights from the front of a vehicle, except for police vehicles, is prohibited to prevent confusion or misdirection among other drivers. This regulation helps ensure that motorists can quickly and accurately identify emergency vehicles, which typically have red lights visible from the front, indicating their presence and authority.

This distinction is critical for maintaining road safety and ensuring that drivers recognize and yield to police vehicles when necessary. Other colors, such as white, green, and amber, may have specific uses (e.g., white lights for standard vehicle headlights, green for volunteer firefighters in some areas, and amber for caution or warning lights), but red remains the only color that is restricted from being visible on the front of non-emergency vehicles.