Cal. PUC § 585

(a) Except as provided in subdivision (d), every public utility and business specified in subdivision (b) shall in any rate proceeding or proceeding establishing a fact or rule that may influence a rate, provide the commission with access to all computer models, as defined in Section 1821, which are used by that public utility or business to substantiate their showing in the proceeding.

(b) The commission shall, by rule or order, with full opportunity for participation by utilities and other affected parties, establish procedures and safeguards governing its access to, and monitoring, verification, and use of, computer models of every public utility and of any business which is a commission regulated subsidiary or affiliate of a public utility with respect to any rate proceeding or proceeding establishing a fact or rule that may influence a rate. The time, place, and manner of commission access shall, to the extent practicable, be the subject of mutual agreement between the commission and the affected utility, and the parties shall make every good faith effort to reach agreement. If an agreement is reached, it shall include, but is not limited to, provisions to reasonably assure the legitimate needs for security of the public utilities’ computer resources. These provisions shall provide for the confidentiality of records, the protection of proprietary information, and the protection of the reasonable expectation of customers of public utilities in the privacy of customer-specific records maintained by the utility. If no agreement is reached, any order issued by the commission requiring computer access shall include, but is not limited to, provisions providing for the security of the utility’s data bases, confidentiality of records, protection of proprietary information, and the privacy of customer-specific records maintained by the utility. The commission shall convene a proceeding to adopt these rules as soon as possible after the operative date of the act adding this section to the code.

(c) This section shall not expand or limit any powers of the commission to prescribe the manner of keeping books, records, and systems of accounts of public utilities and to investigate any of these books, records, systems of accounts, or memoranda under existing law, or any other power of the commission under existing law. Any utility may object to a rule or order of the commission concerning the access prescribed herein under the rules of procedure of the commission consistent with existing law.

(d) This section does not apply to common carriers.