In Clark v. Superior Court, the California Supreme Court examined the interplay between the UCL and Civil Code section 3345, which provides that in an action brought by senior citizens to redress unfair competition, a trier of fact may award up to three times the amount imposed as “a fine, or a civil penalty or other penalty, or any other remedy the purpose or effect of which is to punish or deter.”  Without belaboring the extensive analysis of the legislative histories of the two statutes, the unanimous Court held:

We conclude that because Civil Code section 3345 authorizes the trebling of a remedy only when it is in the nature of a penalty, and because restitution under the unfair competition law is not a penalty, an award of restitution under the unfair competition law — which plaintiffs seek here — is not subject to section 3345's trebling provision.

Slip op., at 2.  You can find more analysis of the reversed decision from the Court of Appeal at The UCL Practitioner.