VOUCHERS.

(a) The comptroller may issue a warrant or initiate an electronic funds transfer to pay or reimburse a travel expense only if a state agency submits to the comptroller a voucher that requests the payment or reimbursement.

(b) A voucher submitted under Subsection (a) is valid only if:

(1) the state agency submitting the voucher approves it in accordance with Chapter 2103 and, if required by law, certifies the voucher; and

(2) the state employee who incurred the travel expense or, if the employee is unavailable, another individual acceptable to the comptroller approves the description, information, and documentation required by Subsection (d) in writing or electronically, except that the employee's approval is not required if another person is required by law to provide the approval.

(c) A voucher must be submitted in the manner required and on the form adopted by the comptroller. The comptroller may require the voucher to be submitted electronically as authorized by Chapter 2103.

(d) A voucher must be supported by:

(1) a description of the official state business performed; and

(2) the information and documentation that the comptroller considers necessary for the comptroller to determine compliance with this chapter, the travel provisions of the General Appropriations Act, and the rules adopted by the comptroller under this chapter.

(e) The comptroller may require a state agency to provide to the comptroller the description, information, and documentation required under Subsection (d):

(1) on the form adopted by the comptroller under Subsection (c);

(2) electronically;

(3) by submitting receipts or other documents; or

(4) by any combination of Subdivisions (1), (2), and (3).