In Connerly v. State Personnel Board (2006) 37 Cal.4th 1169, the plaintiff successfully pursued litigation against six state agencies. Plaintiff sought to invalidate several affirmative action statutes. "The state agencies . . . for the most part opted not to defend the statutes . . . . It fell to various amici curiae advocacy groups that were in favor of affirmative action to defend the state programs and statutes on the merits." (Connerly, supra, 37 Cal.4th at p. 1172.) Pursuant to section 1021.5, the trial court granted the plaintiff's motion for an award of attorney fees. It ordered the state agencies to pay five-sixths and the advocacy groups to pay one-sixth of the award. The advocacy groups contended that they "were not liable for attorney fees in litigation to declare unconstitutional statutes they were not responsible for enacting or enforcing." (Connerly, supra, 37 Cal.4th at p. 1172.) The California Supreme Court concluded that the advocacy groups were not opposing parties within the meaning of section 1021.5. The court reasoned: "Whether they were . . . opposing parties within the meaning of section 1021.5 is ultimately a question of statutory construction. . . . Because the term 'opposing parties' is not defined, it can be assumed that the Legislature was referring to the conventional definition of that term. . . . Generally speaking, the opposing party liable for attorney fees under section 1021.5 has been the defendant person or agency sued, which is responsible for initiating and maintaining actions or policies that are deemed harmful to the public interest and that gave rise to the litigation. By this standard hereafter the Connerly standard, the advocacy groups clearly were not . . . 'opposing parties' because they were responsible neither for enacting nor enforcing the statutes that were judged to be unconstitutional in the underlying litigation." (Connerly, supra, 37 Cal.4th at pp. 1176-1177.) The Supreme Court noted that the advocacy groups had "only an ideological or policy interest in the litigation typical of an amicus curiae." (Connerly, supra, 37 Cal.4th at p. 1181.) The court concluded that "construing section 1021.5 to allow liability against the . . . advocacy groups would be contrary to the judicial policy . . . of welcoming amici curiae in order to 'facilitate informed judicial consideration of a wide variety of information and points of view that may bear on important legal questions.' " (Id., at p. 1182.)