California Code, Health and Safety Code - HSC § 50202

Nothing in this division shall authorize the imposition of rent regulations or controls except by a regulatory contract between the agency or the department, as the case may be, and its housing sponsor or developer, for housing units financed, insured, coinsured or otherwise assisted by the agency or by the department, as the case may be. Except for the federal government, the right to control rent on such units shall reside exclusively in the agency or the department, as the case may be, and the housing sponsor or developer so regulated shall not otherwise be subject to controls on rent imposed by any state or local agency or other local public entity.