In Munson v. Del Taco, Inc., ___ Cal.4th ___ (Jun. 11, 2009), a case involving disability discrimination under the Unruh Civil Rights Act, the Supreme Court discussed the UCL's "unlawful" prong:
Gunther also noted that under its interpretation of section 51, subdivision (f), violations of the ADA that do not involve intentional discrimination might still find a remedy in California law through an action charging an unlawful business practice (Bus. & Prof. Code, §§ 17200, 17203). (Gunther, supra, 144 Cal.App.4th at p. 234.) Though true, that could not have been a purpose of adding subdivision (f) to section 51 of the Civil Code. Violations of federal as well as state and local law may serve as the predicate for an unlawful practice claim under Business and Professions Code section 17200. (See Quacchia v. DaimlerChrysler Corp. (2004) 122 Cal.App.4th 1442, 1450, fn. 5; Saunders v. Superior Court (1994) 27 Cal.App.4th 832, 838-839.) Assuming all other requirements for such an action were met, therefore, violations of the ADA’s accessibility mandate, whether involving intentional discrimination or not, would be remediable through Business and Professions Code sections 17200 and 17203. It did not take incorporation of the ADA mandate into the Unruh Civil Rights Act to achieve that result.
Slip op. at 18-19 (bold added). I believe this is the first time that the Supreme Court, rather than the Court of Appeal, has confirmed that a UCL "unlawful" prong claim may be predicated on violations of federal and local laws as well as state laws. This language is also useful for its confirmation that the UCL carries no "intent" element (or any other element of scienter).