Health and Safety Code §161.082

(a) A person commits an offense if the person, with criminal negligence: (1) sells, gives, or causes to be sold or given a cigarette, e-cigarette, or tobacco product to someone who is younger than 21 years of age; or (2) sells, gives, or causes to be sold or given a cigarette, e-cigarette, or tobacco product to another person who intends to deliver it to someone who is younger than 21 years of age. (b) If an offense under this section occurs in connection with a sale by an employee of the owner of a store in which cigarettes, e-cigarettes, or tobacco products are sold at retail, the employee is criminally responsible for the offense and is subject to prosecution. (c) An offense under this section is a Class C misdemeanor. (d) It is a defense to prosecution under Subsection (a)(1) that the person to whom the cigarette, e-cigarette, or tobacco product was sold or given presented to the defendant apparently valid proof of identification. (e) A proof of identification satisfies the requirements of Subsection (d) if it contains a physical description and photograph consistent with the person's appearance, purports to establish that the person is 21 years of age or older, and was issued by a governmental agency. The proof of identification may include a driver's license issued by this state or another state, a passport, or an identification card issued by a state or the federal government. (f) It is an exception to the application of Subsection (a)(1) that the person to whom the cigarette, e-cigarette, or tobacco product was sold: (1) is at least 18 years of age; and (2) presented at the time of purchase a valid military identification card of the United States military forces or the state military forces.