Tex. Transportation Code § 452.056

(a) An authority may:

(1) acquire, construct, develop, plan, own, operate, and maintain a public transportation system in the territory of the authority, including the territory of a political subdivision;

(2) contract with a municipality, county, or other political subdivision for the authority to provide public transportation services outside the authority; and

(3) lease all or a part of the public transportation system to, or contract for the operation of all or a part of the public transportation system by, an operator.

(b) An authority, as the authority determines advisable, shall determine routes.

(c) The executive committee may submit a referendum for the approval of a power granted by Subsection (a) or (b).

(d) A private operator who contracts with an authority under this chapter is not a public entity for purposes of any law of this state except that an independent contractor of the authority that, on or after June 14, 1989, performs a function of the authority or an entity described by Section 452.0561 that is created to provide transportation services is liable for damages only to the extent that the authority or entity would be liable if the authority or entity itself were performing the function and only for a cause of action that accrues on or after that date.

(e) An authority consisting of one subregion governed by a subregional board created under Subchapter O shall, at least once every five years, evaluate each distinct transportation service the authority provides that generates revenue, including light rail, bus, van, taxicab, and other public transportation services, and determine whether the authority should solicit competitive, sealed bids from other entities to provide these transportation services.