Cal. Gov't Code § 65589.4

(a) An attached housing development shall be a permitted use not subject to a conditional use permit on any parcel zoned for an attached housing development if local law so provides or if it satisfies the requirements of subdivision (b) and either of the following:
1. (1) The attached housing development satisfies the criteria of Section 21159.22, 21159.23, or 21159.24 of the Public Resources Code.
2. (2) The attached housing development meets all of the following criteria:
  1. (A) The attached housing development is subject to a discretionary decision other than a conditional use permit and a negative declaration or mitigated negative declaration has been adopted for the attached housing development under the California Environmental Quality Act (Division 13 (commencing with Section 21000) of the Public Resources Code). If no public hearing is held with respect to the discretionary decision, then the negative declaration or mitigated negative declaration for the attached housing development may be adopted only after a public hearing to receive comments on the negative declaration or mitigated negative declaration.
  2. (B) The attached housing development is consistent with both the jurisdiction’s zoning ordinance and general plan as it existed on the date the application was deemed complete, except that an attached housing development shall not be deemed to be inconsistent with the zoning designation for the site if that zoning designation is inconsistent with the general plan only because the attached housing development site has not been rezoned to conform with the most recent adopted general plan.
  3. (C) The attached housing development is located in an area that is covered by one of the following documents that has been adopted by the jurisdiction within five years of the date the application for the attached housing development was deemed complete:
    1. (i) A general plan.
    2. (ii) A revision or update to the general plan that includes at least the land use and circulation elements.
    3. (iii) An applicable community plan.
    4. (iv) An applicable specific plan.
  4. (D) The attached housing development consists of not more than 100 residential units with a minimum density of not less than 12 units per acre or a minimum density of not less than eight units per acre if the attached housing development consists of four or fewer units.
  5. (E) The attached housing development is located in an urbanized area as defined in Section 21071 of the Public Resources Code or within a census-defined place with a population density of at least 5,000 persons per square mile or, if the attached housing development consists of 50 or fewer units, within an incorporated city with a population density of at least 2,500 persons per square mile and a total population of at least 25,000 persons.
  6. (F) The attached housing development is located on an infill site as defined in Section 21061.3 of the Public Resources Code.
(b) At least 10 percent of the units of the attached housing development shall be available at affordable housing cost to very low income households, as defined in Section 50105 of the Health and Safety Code, or at least 20 percent of the units of the attached housing development shall be available at affordable housing cost to lower income households, as defined in Section 50079.5 of the Health and Safety Code, or at least 50 percent of the units of the attached housing development available at affordable housing cost to moderate-income households, consistent with Section 50052.5 of the Health and Safety Code. The developer of the attached housing development shall provide sufficient legal commitments to the local agency to ensure the continued availability and use of the housing units for very low, low-, or moderate-income households for a period of at least 30 years.
(c) Nothing in this section shall prohibit a local agency from applying design and site review standards in existence on the date the application was deemed complete.
(d) The provisions of this section are independent of any obligation of a jurisdiction pursuant to subdivision (c) of Section 65583 to identify multifamily sites developable by right.
(e) This section does not apply to the issuance of coastal development permits pursuant to the California Coastal Act of 1976 (Division 20 (commencing with Section 30000) of the Public Resources Code).
(f) This section does not relieve a public agency from complying with the California Environmental Quality Act (Division 13 (commencing with Section 21000) of the Public Resources Code) or relieve an applicant or public agency from complying with the Subdivision Map Act (Division 2 (commencing with Section 66410)).
(g) This section is applicable to all cities and counties, including charter cities, because the Legislature finds that the lack of affordable housing is of vital statewide importance, and thus a matter of statewide concern.
(h) For purposes of this section, “attached housing development” means a newly constructed or substantially rehabilitated structure containing two or more dwelling units and consisting only of residential units, but does not include an accessory dwelling unit, as defined in subdivision (a) of Section 66313, or the conversion of an existing structure to condominiums.