Local Government Code §157.021

(a) In a county with a population of 265,000 or more, the commissioners court may adopt and enforce uniform rules on the hours of work of department heads, assistants, deputies, and other employees whose compensation is set or approved by the court. (b) The commissioners court of any county may adopt and enforce uniform rules on overtime and compensatory time for department heads, assistants, deputies, and other employees whose compensation is set or approved by the commissioners court. The rules may: (1) prohibit unbudgeted overtime, except when the commissioners court or an elected county or district officer declares an emergency; and (2) require that emergency overtime be reported to the county auditor and the commissioners court.