Cal. Business and Professions Code § 7521

A private investigator within the meaning of this chapter is a person, other than an insurance adjuster subject to the provisions of Chapter 1 (commencing with Section 14000) of Division 5 of the Insurance Code, who, for any consideration whatsoever engages in business or accepts employment to furnish or agrees to furnish any person to protect persons pursuant to Section 7521.5, or engages in business or accepts employment to furnish, or agrees to make, or makes, any investigation for the purpose of obtaining, information with reference to: (a) Crime or wrongs done or threatened against the United States of America or any state or territory of the United States of America. (b) The identity, habits, conduct, business, occupation, honesty, integrity, credibility, knowledge, trustworthiness, efficiency, loyalty, activity, movement, whereabouts, affiliations, associations, transactions, acts, reputation, or character of any person. (c) The location, disposition, or recovery of lost or stolen property. (d) The cause or responsibility for fires, libels, losses, accidents, or damage or injury to persons or to property. (e) Securing evidence to be used before any court, board, officer, or investigating committee. For the purposes of this section, a private investigator is any person, as defined in Section 7512.3, acting for the purpose of investigating, obtaining, and reporting to any employer, or an agent designated by the employer, information concerning the employer’s employees involving questions of integrity, honesty, breach of rules, or other standards of performance of job duties. This section does not apply to a public utility regulated by the Public Utilities Commission, or its employees.