The Judge of Probate of Crenshaw County shall perform all duties relative to the assessment and collection of taxes on motor vehicles, motor vehicle titles, and non-motorized vehicles in Crenshaw County which the revenue commissioner is required under the law to perform. The revenue commissioner shall be relieved of all duties and responsibilities relative to the assessment and collection of taxes on motor vehicles, motor vehicle titles, and non-motorized vehicles, and the judge of probate shall have all the duties and responsibilities relative to the assessment and collection of taxes and issuance of motor vehicle licenses and titles for motorized and non-motorized vehicles. For purposes of this subpart, the term "motor vehicle" shall mean the same as defined in Article 5, commencing with Section 40-12-240, Chapter 12, Title 40.