California Code, Government Code - GOV § 11349

(a) “Necessity” means the record of the rulemaking proceeding demonstrates by substantial evidence the need for a regulation to effectuate the purpose of the statute, court decision, or other provision of law that the regulation implements, interprets, or makes specific, taking into account the totality of the record.  For purposes of this standard, evidence includes, but is not limited to, facts, studies, and expert opinion.

(b) “Authority” means the provision of law which permits or obligates the agency to adopt, amend, or repeal a regulation.

(c) “Clarity” means written or displayed so that the meaning of regulations will be easily understood by those persons directly affected by them.

(d) “Consistency” means being in harmony with, and not in conflict with or contradictory to, existing statutes, court decisions, or other provisions of law.

(e) “Reference” means the statute, court decision, or other provision of law which the agency implements, interprets, or makes specific by adopting, amending, or repealing a regulation.

(f) “Nonduplication” means that a regulation does not serve the same purpose as a state or federal statute or another regulation.  This standard requires that an agency proposing to amend or adopt a regulation must identify any state or federal statute or regulation which is overlapped or duplicated by the proposed regulation and justify any overlap or duplication.  This standard is not intended to prohibit state agencies from printing relevant portions of enabling legislation in regulations when the duplication is necessary to satisfy the clarity standard in paragraph (3) of subdivision (a) of Section 11349.1.  This standard is intended to prevent the indiscriminate incorporation of statutory language in a regulation.