Washington Revised Code Title 46. Motor Vehicles § 46.37.100. Color of clearance lamps, side marker lamps, backup lamps, and reflectors

(1) Front clearance lamps and those marker lamps and reflectors mounted on the front or on the side near the front of a vehicle shall display or reflect an amber color.

(2) Rear clearance lamps and those marker lamps and reflectors mounted on the rear or on the sides near the rear of a vehicle shall display or reflect a red color.

(3) All lighting devices and reflectors mounted on the rear of any vehicle shall display or reflect a red color, except the stop lamp or other signal device, which may be red, amber, or yellow, and except that on any vehicle forty or more years old, or on any motorcycle regardless of age, the taillight may also contain a blue or purple insert of not more than one inch in diameter, and except that the light illuminating the license plate shall be white and the light emitted by a backup lamp shall be white or amber. However, for commercial motor vehicles defined in RCW 46.32.005, stop lamps must be red and other signal devices must be red or amber.