California Code, Business and Professions Code - BPC § 22949.66

(a) A defendant against whom an action is brought under Section 22949.65 does not have standing to assert the right of another individual to keep and bear arms under the Second Amendment to the United States Constitution as a defense to liability under that section unless either of the following is true:

(b) A defendant in an action brought under Section 22949.65 may assert an affirmative defense to liability under this section if both of the following are true:

(c) Nothing in this section shall in any way limit or preclude a defendant from asserting the defendant's personal constitutional rights as a defense to liability under Section 22949.65, and a court shall not award relief under Section 22949.65 if the conduct for which the defendant has been sued was an exercise of a state or federal constitutional right that personally belongs to the defendant.