California Code, Government Code - GOV § 65863.6

(a) In carrying out this chapter, each county and city shall consider the effect of ordinances adopted pursuant to this chapter on the housing needs of the region in which the local jurisdiction is situated and balance these needs against the public service needs of its residents and available fiscal and environmental resources. Any ordinance adopted pursuant to this chapter which, by its terms, limits the number of housing units which may be constructed on an annual basis shall contain findings as to the public health, safety, and welfare of the city or county to be promoted by the adoption of the ordinance which justify reducing the housing opportunities of the region.

(b) Notwithstanding Section 65803, this section shall also apply to a charter city.