Tex. Elec. Code § 13.045

Except as otherwise provided by law, the chief executive of a state agency with approval of the agency's governing body, if any, the chief executive of a department of a city with approval of the city's governing body, or a county officer may permit an officer or employee under the chief executive's or officer's supervision who is a volunteer deputy registrar to engage in official registration activities during working hours on the premises under the chief executive's or officer's control.