California Code, Government Code - GOV § 65589

(a) Nothing in this article shall require a city, county, or city and county to do any of the following:

(b) Nothing in this article shall be construed to be a grant of authority or a repeal of any authority which may exist of a local government to impose rent controls or restrictions on the sale of real property.

(c) Nothing in this article shall be construed to be a grant of authority or a repeal of any authority which may exist of a local government with respect to measures that may be undertaken or required by a local government to be undertaken to implement the housing element of the local general plan.

(d) The provisions of this article shall be construed consistent with, and in promotion of, the statewide goal of a sufficient supply of decent housing to meet the needs of all Californians.