(a) The executive commissioner shall adopt a policy regarding random testing and reasonable suspicion testing for the illegal use of drugs by a center employee.
(b) The policy adopted under Subsection (a) must provide that a center employee may be terminated solely on the basis of a single positive test for illegal use of a controlled substance. The policy must establish an appeals process for a center employee who tests positively for illegal use of a controlled substance.

(c) The director of a state supported living center or the superintendent of the Rio Grande State Center shall enforce the policy adopted under Subsection (a) by performing necessary drug testing of the center employees for the use of a controlled substance as defined by § 481.002.
(d) Testing under this section may be performed on a random basis or on reasonable suspicion of the use of a controlled substance.
(e) For purposes of this section, a report made under § 555.023 is considered reasonable suspicion of the use of a controlled substance.