SECTION 1. Section 15 of chapter 85 of the Massachusetts General Laws, as appearing in the 2006 Official Edition, is hereby amended by striking out lines 1 through 4 and inserting in place thereof the following:—

“Section 15. Every vehicle, whether stationary or in motion, on any public way, shall have attached to it a light or lights (i.e., headlight(s) and taillight(s)) which shall be turned on by the vehicle operator so displayed as to be visible from the front and rear during the period of one half-hour after sunset to one half-hour before sunrise; provided, such lamps shall be turned on by the vehicle operator at all other times when, due to insufficient light or unfavorable atmospheric conditions, visibility is reduced such that persons or vehicles on the roadway are not clearly discernible at a distance of five hundred feet, or the vehicle’s windshield wipers are needed.”