Cal. Bus. & Prof. Code § 7090
The registrar may upon his or her own motion and shall upon the verified complaint in writing of any person, investigate the actions of any applicant, contractor, or home improvement salesperson within the state and may deny the licensure or the renewal of licensure of, or cite, temporarily suspend, or permanently revoke any license or registration if the applicant, licensee, or registrant, is guilty of or commits any one or more of the acts or omissions constituting causes for disciplinary action.
The registrar may proceed to take disciplinary action as in this article provided against an applicant or a person licensed or registered under the provisions of this chapter even though the grounds or cause for such disciplinary action arose upon projects or while the applicant, licensee, or registrant was acting in a capacity or under circumstances or facts which, under the provisions of Sections 7044, 7045, 7046, and 7048, would otherwise exempt the person or his or her operations from the provisions of this chapter.
Notwithstanding any provision of this chapter, if the registrar finds that any contractor licensed or registered under the provisions of this chapter has willfully and deliberately violated any state or local law relating to the issuance of building permits, other than failure to obtain a county or city permit for repair, maintenance, and adjustment of equipment where such repair, maintenance, or adjustment is valued at less than five hundred dollars ($500) for labor or materials, or where the repair of a part or component part of mechanical equipment consists of replacing such part or component part of mechanical equipment in need of repair with the identical part or component part, the registrar shall take disciplinary action against the contractor's license in accordance with this chapter.
For the purpose of this section, there shall be a rebuttable presumption affecting the burden of proof that construction performed without a permit is a willful and deliberate violation.
For the purposes of this section, with respect to administrative proceedings or hearings to suspend or revoke a contractor's license, the registrar at all times shall have the burden of proof to establish by clear and convincing evidence that he or she is entitled to the relief sought in the petition.
Ca. Bus. and Prof'l. Code § 7090