RCW 46.37.280: Special restrictions on lamps.

(1) During the times specified in RCW 46.37.020, any lighted lamp or illuminating device upon a motor vehicle, other than head lamps, spot lamps, auxiliary lamps, flashing turn signals, emergency vehicle warning lamps, warning lamps authorized by the state patrol and school bus warning lamps, which projects a beam of light of an intensity greater than three hundred candlepower shall be so directed that no part of the high intensity portion of the beam will strike the level of the roadway on which the vehicle stands at a distance of more than seventy-five feet from the vehicle.

(2) Except as required in RCW 46.37.190 no person shall drive or move any vehicle or equipment upon any highway with any lamp or device thereon displaying a red light visible from directly in front of the center thereof.

(3) Flashing lights are prohibited except as required in RCW 46.37.190, 46.37.200, 46.37.210, 46.37.215, and 46.37.300, warning lamps authorized by the state patrol, and light-emitting diode flashing taillights on bicycles.