Texas Government Code - GOV'T § 301.019. Joint General Investigating Committee Hearings

(a) On a majority vote of each general investigating committee, the committees may conduct joint hearings and investigations.  The committees may adopt joint rules to govern the hearings.

(b) If the general investigating committees conduct joint inquiries or investigations, the chairman of the senate committee shall be the chairman and the chairman of the house committee shall be the vice-chairman.

(c) A majority of the members from each house's committee constitutes a quorum of a joint general investigating committee.