Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 90, § 7AA

A passenger in a motor vehicle on any way who is under the age of 8 shall be fastened and secured by a child passenger restraint, unless such passenger measures more than 57 inches in height. The child passenger restraint shall be properly fastened and secured according to the manufacturer's instructions.

Unless required to be properly fastened and secured by a child passenger restraint under the preceding paragraph, a passenger in a motor vehicle on any way that is under the age of 13 shall wear a safety belt which is properly adjusted and fastened according to the manufacturer's instructions.

The provisions of this section shall not apply to any such child who is: (1) riding as a passenger in a school bus; (2) riding as a passenger in a motor vehicle made before July first, nineteen hundred and sixty-six, that is not equipped with safety belts; (3) physically unable to use either a conventional child passenger restraint or a child restraint specifically designed for children with special needs; provided, however, that such condition is duly certified in writing by a physician who shall state the nature of the disability as well as the reasons such restraints are inappropriate; provided, further, that no such certifying physician shall be subject to liability in a civil action for the issuance of or for the failure to issue such certificate. An operator of a motor vehicle who violates the provisions of this section shall be subject to a fine of not more than twenty-five dollars; provided, however, that said twenty-five dollar fine shall not apply to an operator of a motor vehicle licensed as a taxi cab not equipped with a child passenger restraint device.

A violation of this section shall not be used as evidence of contributory negligence in any civil action.

A person who receives a citation for a violation of any of the provisions of this section may contest such citation pursuant to section three of chapter ninety C. A violation of this section shall not be deemed to be a conviction of a moving violation of the motor vehicle laws for the purpose of determining surcharges on motor vehicle premiums pursuant to section one hundred and thirteen B of chapter one hundred and seventy-five.