POLICE WARNING LIGHTS AND VEHICLE HEADLIGHTS - TOO BRIGHT

Police lights in many areas are being criticized for being too bright, causing a hazard at night to drivers and being unnecessary. While police lights are generally bright enough in the daytime, maintaining that brightness at night is questionable. The newer police emergency lights are bright at night to warn other drivers to get out of the way of an approaching emergency vehicle or to give a wide berth to one that is stationary. However, a bright light source in a person's field of view can reduce their ability to see other objects, which may be exacerbated by rain, windshields, or eyeglasses. A study distinguished between 'disability glare', where a driver may be temporarily blinded and unable to see hazards in the road, and 'discomfort glare', which is a more general effect from lights which may cause motorists to avert their eyes. Most police cars cannot control the brightness of the lights.