(1) Except as otherwise provided in this section, "motor vehicle" as used in this section means every vehicle designed to carry fifteen (15) or fewer passengers and used for the transportation of persons, but the term does not include:
(a) Motorcycles;
(b) Motor-driven cycles; or (c) Farm trucks registered for agricultural use only and having a gross weight of one (1) ton or more.
(2) A person shall not sell any new motor vehicle in this state nor shall any person make application for registering a new motor vehicle in this state unless the front or forward seat or seats have adequate anchors or attachments secured to the floor and/or sides to the rear of the seat or seats to which seat belts may be secured.
(3) (a) Any driver of a motor vehicle, when transporting a child of forty (40) inches in height or less in a motor vehicle operated on the roadways, streets, and highways of this state, shall have the child properly secured in a child restraint system of a type meeting federal motor vehicle safety standards.
(b) Any driver of a motor vehicle, when transporting a child under the age of eight (8) years who is between forty (40) inches and fifty-seven (57) inches in height in a motor vehicle operated on the roadways, streets, and highways of this state, shall have the child properly secured in a child booster seat. A child of any age who is greater than fifty-seven (57) inches in height shall not be required to be secured in a child booster seat under this section.
(4) As used in this section:
(a) "Child restraint system" means any device manufactured to transport children in a motor vehicle which conforms to all applicable federal motor vehicle safety standards; and (b) "Child booster seat" means a child passenger restraint system that meets the standards set forth in 49 C.F.R. Part 571 that is designed to elevate a child to properly sit in a federally approved lap-and-shoulder belt system.
(5) Failure to use a child passenger restraint system or a child booster seat shall not be considered as contributory negligence, nor shall such failure to use a passenger restraint system or booster seat be admissible as evidence in the trial of any civil action. Failure of any person to wear a seat belt shall not constitute negligence per se.
(6) A person shall not operate a motor vehicle manufactured after 1981 on the public roadways of this state unless the driver and all passengers are wearing a properly adjusted and fastened seat belt, unless the passenger is a child who is secured as required in subsection (3) of this section. The provisions of this subsection shall not apply to:
(a) A person who has in his possession at the time of the conduct in question a written statement from a physician, advanced practice registered nurse, or licensed chiropractor that he is unable, for medical or physical reasons, to wear a seat belt; or (b) A letter carrier of the United States postal service while engaged in the performance of his duties.
(7) A conviction for a violation of subsection (6) of this section shall not be transmitted by the court to the Transportation Cabinet. The Transportation Cabinet shall not include a conviction for a violation of subsection (6) of this section as part of any person's driving history record.
(8) The provisions of subsection (6) of this section shall supersede any existing local ordinance involving the use of seat belts. No ordinance contrary to subsection (6) of this section may be enacted by any unit of local government.