Tex. Educ. Code § 12.018

The charter commission shall submit the proposed charter to the commissioner. As soon as practicable, but not later than the 30th day after the date the commissioner receives the proposed charter, the commissioner shall review the proposed charter to ensure that the proposed charter complies with any applicable laws and shall recommend to the charter commission any modifications necessary. If the commissioner does not act within the prescribed time, the proposed charter is approved.