Texas Transportation Code - TRANSP § 545.060. Driving on Roadway Laned for Traffic

(a) An operator on a roadway divided into two or more clearly marked lanes for traffic:

(b) If a roadway is divided into three lanes and provides for two-way movement of traffic, an operator on the roadway may not drive in the center lane except:

(c) Without regard to the center of the roadway, an official traffic-control device may be erected directing slow-moving traffic to use a designated lane or designating lanes to be used by traffic moving in a particular direction.

(d) Official traffic-control devices prohibiting the changing of lanes on sections of roadway may be installed.