California Evidence Code
Evidence Code section 972
A married person does not have a privilege under this article in:
(a) A proceeding brought by or on behalf of one spouse against the other spouse.
(b) A proceeding to commit or otherwise place his or her spouse or his or her spouse's property, or both, under the control of another because of the spouse's alleged mental or physical condition.
(c) A proceeding brought by or on behalf of a spouse to establish his or her competence.
(d) A proceeding under the Juvenile Court Law, Chapter 2 (commencing with Section 200) of Part 1 of Division 2 of the Welfare and Institutions Code .
(e) A criminal proceeding in which one spouse is charged with:
(1) A crime against the person or property of the other spouse or of a child, parent, relative, or cohabitant of either, whether committed before or during marriage.
(2) A crime against the person or property of a third person committed in the course of committing a crime against the person or property of the other spouse, whether committed before or during marriage.
(4) A crime defined by Section 270 or 270a of the Penal Code .
(f) A proceeding resulting from a criminal act which occurred prior to legal marriage of the spouses to each other regarding knowledge acquired prior to that marriage if prior to the legal marriage the witness spouse was aware that his or her spouse had been arrested for or had been formally charged with the crime or crimes about which the spouse is called to testify.
(g) A proceeding brought against the spouse by a former spouse so long as the property and debts of the marriage have not been adjudicated, or in order to establish, modify, or enforce a child, family or spousal support obligation arising from the marriage to the former spouse; in a proceeding brought against a spouse by the other parent in order to establish, modify, or enforce a child support obligation for a child of a nonmarital relationship of the spouse; or in a proceeding brought against a spouse by the guardian of a child of that spouse in order to establish, modify, or enforce a child support obligation of the spouse. The married person does not have a privilege under this subdivision to refuse to provide information relating to the issues of income, expenses, assets, debts, and employment of either spouse, but may assert the privilege as otherwise provided in this article if other information is requested by the former spouse, guardian, or other parent of the child.
Any person demanding the otherwise privileged information made available by this subdivision, who also has an obligation to support the child for whom an order to establish [FN1], modify, or enforce child support is sought, waives his or her marital privilege to the same extent as the spouse as provided in this subdivision.