Rev. & Tax. Code, § 19556

(a) The Franchise Tax Board may disclose to persons described in paragraphs (1) to (4), inclusive, tax return and return information solely for use in an action or proceeding affecting the personnel rights of an employee or former employee, or in preparation of the action or proceeding, but only to the extent the Franchise Tax Board determines that the return or return information is, or may be, relevant and material to the action or proceeding. Tax return and return information may be disclosed pursuant to this section to any of the following persons:

(1) An employee or former employee of the Franchise Tax Board who is, or may be, a party to an administrative action or proceeding affecting the personnel rights of that employee or former employee.

(2) Upon written request by the employee or former employee, to the employee’s or former employee’s duly authorized legal representative.

(3) Officers and employees of the Franchise Tax Board for use in any action or proceeding affecting the rights of an employee or former employee, to the extent necessary to advance or protect the interests of the State of California.

(4) An administrative law judge, administrative board member, judge, or justice, or authorized officer or employee thereof, in connection with an administrative hearing, adjudication, or appeal thereof, related to an action or proceeding affecting the personnel rights of an employee or former employee.

(b) For purposes of this section, an action or proceeding affecting the personnel rights of an employee or former employee of the Franchise Tax Board means an action proceeding arising under either of the following:

(1) The State Civil Service Act (Part 2 (commencing with Section 18500) of Division 5 of the Government Code).

(2) The Ralph C. Dills Act (Chapter 10.3 (commencing with Section 3512) of Division 4 of Title 1 of the Government Code).

(c) Any unauthorized disclosure by a person described in paragraphs (1) to (4), inclusive, of subdivision (a) of any tax return or return information disclosed to that person pursuant to this section shall be subject to criminal penalty and civil liability under this part for that unauthorized disclosure.