The Department of Motor Vehicles may issue special motor vehicle license plates to members of municipal and county councils, county coroners, and mayors of this State for private passenger motor vehicles owned by them. The department also may issue special motor vehicle license plates to former members of the General Assembly who are eligible to receive retirement benefits under the General Assembly Retirement System for private passenger motor vehicles owned by them. The biennial fee for these special license plates is the same as the fee provided in Section 56-3-2020, and only one plate may be issued to a councilman, coroner, mayor, or member of the General Assembly who is receiving retirement benefits. The plate must be issued or revalidated biennially for the regular registration and licensing period.