California Code, Business and Professions Code - BPC § 25750

(a) The department shall make and prescribe those reasonable rules as may be necessary or proper to carry out the purposes and intent of Section 22 of Article XX of the California Constitution and to enable it to exercise the powers and perform the duties conferred upon it by that section or by this division, not inconsistent with any statute of this state, including particularly this division and Chapter 5 (commencing with Section 11500) of Part 1 of Division 3 of Title 2 of the Government Code.

(b) Any regulation which excludes nude persons from licensed premises shall not apply to a nude person at licensed premises located at a nudist resort or nudist campground which was in existence prior to January 1, 1977, and whose operation is in conformance with local land use regulations.

(c) Subdivision (b) is applicable only in a county where the board of supervisors of the county in which the licensed premises is located adopts an ordinance or resolution making subdivision (b) applicable in that county, and the sheriff of that county certifies that no extraordinary police problem would be created thereby.