(1) It shall be unlawful to operate a slow moving vehicle on the highways at the following times and under the following circumstances:(a)
From one-half (1/2) hour after sunset to one-half (1/2) hour before sunrise, unless the vehicle or equipment is equipped with lights as required by section
49-916, Idaho Code;
(b) At a speed in excess of twenty-five (25) miles per hour, unless the vehicle or equipment, including towed units of farm equipment, is designed to safely travel at speeds in excess of twenty-five (25) miles per hour, but no such vehicle or equipment shall exceed the posted maximum speed limit and shall be operated by a licensed driver;
(c) In such a manner as to obstruct the free movement of traffic on the highways.
(2) A slow moving vehicle shall be equipped with a braking system and with a mechanical signaling device as required for other similarly constructed vehicles.
(3) All slow moving vehicles, farm tractors, road rollers and implements of husbandry shall have affixed at the rear of the vehicle an emblem identifying them as slow moving equipment. The Idaho traffic safety commission shall recommend to the board the minimum standards for the emblem.
(4) Emergency and snow removal vehicles owned and operated by the state or its political subdivisions when en route to, from, or in the performance of activities essential to the public safety, shall be exempt from the provisions of paragraphs (a) and (c) of subsection (1) of this section.
Idaho Statutes