Cal. Civil Code § 1788.13

No debt collector shall collect or attempt to collect a covered debt by means of the following practices: (a) Any communication with the debtor other than in the name either of the debt collector or the person on whose behalf the debt collector is acting. (b) Any false representation that any person is an attorney or counselor at law. (c) Any communication with a debtor in the name of an attorney or counselor at law or upon stationery or like written instruments bearing the name of the attorney or counselor at law, unless that communication is by an attorney or counselor at law or shall have been approved or authorized by that attorney or counselor at law. (d) The representation that any debt collector is vouched for, bonded by, affiliated with, or is an instrumentality, agent or official of any federal, state or local government or any agency of federal, state or local government, unless the collector is actually employed by the particular governmental agency in question and is acting on behalf of that agency in the debt collection matter. (e) The false representation that the covered debt may be increased by the addition of attorney’s fees, investigation fees, service fees, finance charges, or other charges if, in fact, those fees or charges may not legally be added to the existing obligation. (f) The false representation that information concerning a debtor’s failure or alleged failure to pay a covered debt has been or is about to be referred to a consumer reporting agency. (g) The false representation that a debt collector is a consumer reporting agency. (h) The false representation that collection letters, notices or other printed forms are being sent by or on behalf of a claim, credit, audit, or legal department. (i) The false representation of the true nature of the business or services being rendered by the debt collector. (j) The false representation that a legal proceeding has been, is about to be, or will be instituted unless payment of a covered debt is made. (k) The false representation that a covered debt has been, is about to be, or will be sold, assigned, or referred to a debt collector for collection. (l) Any communication by a collection agency to a debtor demanding money unless the claim is actually assigned to the collection agency.