Chapter 10. Res Judicata of California Revenue And Taxation Code >> Division 2. >> Part 10.2. >> Chapter 10.

In the determination of any issue of law or fact under Part 10 (commencing with Section 17001), Part 11 (commencing with Section 23001), or this part, neither the Franchise Tax Board nor any officer or agency having any administrative duties under this part nor any court is bound by the determination of any other officer or administrative agency of the state.

(a) In the determination of any case arising under this part, the rule of res judicata is applicable only if the liability involved is for the same year as was involved in another case previously determined.
  (b) Notwithstanding the holding in Pope Estate Company v. Johnson, 43 Cal. App. 2d 170, in any action filed pursuant to Section 19382 (relating to taxpayer suits for refund), in addition to the defenses or relief sought in the action, the Franchise Tax Board shall assert in defense only those unpaid liabilities of the taxpayer for the same year which are evidenced by any of the following:
  (1) A final proposed assessment.
  (2) A notice of tax due.
  (3) A final notice of action. In addition, any refund claim of a taxpayer for the same year resulting from a federal audit adjustment made subsequent to the filing of the action need not be asserted by the taxpayer in that action.