California Code, Revenue and Taxation Code - RTC § 19548

(a) The Franchise Tax Board, upon request by the California Parent Locator Service, may disclose to the California Parent Locator Service, pursuant to Section 17505 or 17506 of the Family Code, any taxpayer return information that may be of assistance in locating alleged abducting or absent parents, spouses, or former spouses, in enforcing their liability for child support or the liability for spousal support, in establishing a parent and child relationship, and in locating and returning abducted children to their parents.

(b) Information disclosed to the California Parent Locator Service pursuant to subdivision (a) shall be disseminated by the California Parent Locator Service only as provided for by, and only for the purposes specified in, Section 17505 or 17506 of the Family Code.