Tex. Util. Code § 39.609
Debt obligations issued pursuant to this subchapter, including any bonds, are not a debt or obligation of the state and are not a charge on its full faith and credit or taxing power. The state pledges, however, for the benefit and protection of financing parties and the independent organization that it will not take or permit any action that would impair the value of default property, or reduce, alter, or impair the default charges to be imposed, collected, and remitted to financing parties, until the principal, interest and premium, and any other charges incurred and contracts to be performed in connection with the related debt obligations have been paid and performed in full. Any party issuing a debt obligation under this subchapter is authorized to include this pledge in any documentation relating to the obligation.
Tex. Util. Code § 39.609