(a) In this section, “controlled substance” and “marihuana” have the meanings assigned by § 481.002, Health and Safety Code.
(b) This subchapter does not require a group health benefit plan to provide coverage for the treatment of:
(1) addiction to a controlled substance or marihuana that is used in violation of law; or
(2) mental illness that results from the use of a controlled substance or marihuana in violation of law.