Tex. Transp. Code § 545.103 : TRANSPORTATION CODE — VEHICLES AND TRAFFIC — RULES OF THE ROAD — OPERATION AND MOVEMENT OF VEHICLES — TURNING AND SIGNALS FOR STOPPING AND TURNING — Safely Turning

An operator may not turn the vehicle to enter a private road or driveway, otherwise turn the vehicle from a direct course, or move right or left on a roadway unless movement can be made safely.