Cal. Rev. & Tax. Code § 43159.2

(a) Under regulations prescribed by the board, with respect to a fee imposed pursuant to Section 105310 of the Health and Safety Code, if:
1. (1) A fee liability due on a notice of determination or other billing document for collection of the fee under this part was unpaid and the nonpayment of the fee liability is attributable to one spouse.
2. (2) The other spouse establishes that he or she did not know of, and had no reason to know of, that nonpayment.
3. (3) Taking into account whether or not the other spouse significantly benefited directly or indirectly from the nonpayment and taking into account all other facts and circumstances, it is inequitable to hold the other spouse liable for the deficiency in the fee attributable to that nonpayment,
  then the other spouse shall be relieved of liability for the fee (including interest, penalties, and other amounts) to the extent that the liability is attributable to that nonpayment of the fee.
(b) For purposes of this section, the determination of the spouse to whom items of nonpayment are attributable shall be made without regard to community property laws.
(c) This section shall apply to all calendar years subject to the provisions of this part, but shall not apply to any calendar year that is more than five years from the final date on the board-issued determination or other similar billing document for collection of the fee, five years from the due date for payment on the billing, or one year from the first contact with the spouse making a claim under this section; or that has been closed by res judicata, whichever is later.
(d) For purposes of paragraph (2) of subdivision (a), “reason to know” means whether or not a reasonably prudent person would have had reason to know of the understatement or nonpayment.
(e) For purposes of this section, with respect to a failure to pay a notice of determination or similar billing document for collection of the fee, “attributable to one spouse” may be determined by whether a spouse rendered substantial service as a feepayer with respect to a fee imposed under Section 105310 of the Health and Safety Code to which the nonpayment is attributable. If neither spouse rendered substantial services as a feepayer, then the attribution of the nonpayment shall be treated as community property.
(f) Under procedures prescribed by the board, if, taking into account all the facts and circumstances, it is inequitable to hold the other spouse liable for any unpaid fee or any deficiency (or any portion of either) attributable to any item for which relief is not available under subdivision (a), the board may relieve the other spouse of that liability.
(g) For purposes of this section, registered domestic partners, as defined in Section 297 of the Family Code, have the same rights, protections, and benefits as provided by this section, and are subject to the same responsibilities, obligations, and duties as imposed by this section, as are granted to and imposed upon spouses.
(h) The relief provided by this section shall apply retroactively to liabilities arising prior to the effective date of this section.