Government Code §551.144

(a) A member of a governmental body commits an offense if a closed meeting is not permitted under this chapter and the member knowingly: (1) calls or aids in calling or organizing the closed meeting, whether it is a special or called closed meeting; (2) closes or aids in closing the meeting to the public, if it is a regular meeting; or (3) participates in the closed meeting, whether it is a regular, special, or called meeting. (b) An offense under Subsection (a) is a misdemeanor punishable by: (1) a fine of not less than $100 or more than $500; (2) confinement in the county jail for not less than one month or more than six months; or (3) both the fine and confinement. (c) It is an affirmative defense to prosecution under Subsection (a) that the member of the governmental body acted in reasonable reliance on a court order or a written interpretation of this chapter contained in an opinion of a court of record, the attorney general, or the attorney for the governmental body.