Texas Government Code - GOV'T § 325.018. Subpoena Power

(a) The commission may issue process to compel the attendance of witnesses and the production of books, records, papers, and other objects necessary or proper for the purposes of the commission proceedings.  The process may be served on a witness at any place in this state.

(b) If a majority of the commission directs the issuance of a subpoena, the chairman shall issue the subpoena in the name of the commission.

(c) If the chairman is absent, the chairman's designee may issue a subpoena or other process in the same manner as the chairman.

(d) If necessary to obtain compliance with a subpoena or other process, the commission may issue attachments.  The attachments may be addressed to and served by any peace officer in this state.

(e) Testimony taken under subpoena must be reduced to writing and given under oath subject to the penalties of perjury.

(f) A witness who attends a commission proceeding under process is entitled to the same mileage and per diem as a witness who appears before a grand jury in this state.