The motor vehicle registration plates authorized by this act shall be issued upon proof, satisfactory to the director, that the vehicle for which the plates are issued is owned or leased by a freeholder, surrogate, county clerk, county register of deeds and mortgages, elected county executive, sheriff or other county officer. The fee for such plates shall be $15.00 in addition to the fees otherwise prescribed by law for the registration of motor vehicles.
N.J.S. § 39:3-27.30