22 Tex. Admin. Code § 213.12
A witness who is not a party to the proceeding and who is subpoenaed to appear at a deposition or hearing or to produce books, papers, or other objects, shall be entitled to receive reimbursement for expenses incurred in complying with the subpoena as set by the legislature in the APA, Texas Government Code Annotated §2001.103. In addition, a subpoenaed witness is entitled to thirty dollars ($30) for each day or part of a day that the person is necessarily present, and 48.5 cents for each mile for going to and returning from the place of the hearing or deposition if the place is more than 25 miles from the person's place of residence, and the person uses the person's personally owned or leased motor vehicle for the travel.
Source Note:The provisions of this §213.12 adopted to be effective August 15, 2002, 27 TexReg 7107; amended to be effective January 8, 2008, 33 TexReg 179.