Sec. 3.7. Notwithstanding sections 2 and 3.6 of this chapter, a person may operate a motor vehicle in which there is a child who weighs more than forty (40) pounds and who is properly restrained and fastened by a lap safety belt if:
(1) the motor vehicle is not equipped with lap and shoulder safety belts; or
(2) not including the operator's seat and the front passenger seat:
(A) the motor vehicle is equipped with one (1) or more lap and shoulder safety belts; and
(B) all the lap and shoulder safety belts are being used to properly restrain other children who are less than sixteen (16) years of age.