Tex. Loc. Gov't Code § 157.906
(a) A county shall pay a peace officer employed by the county for an appearance as a witness in a criminal suit, a civil suit, or an administrative proceeding in which the county or other political subdivision or government agency is a party in interest if the appearance:
Added by Acts 2009, 81st Leg., R.S., Ch. 412 (H.B. 1960), Sec. 3, eff. June 19, 2009.