California Code, Revenue and Taxation Code - RTC § 38575

(a) For the purpose of collecting taxes, interest, additions to tax, and penalties, the board may enter into agreements with one or more private persons, companies, associations, or corporations providing debt collection services outside this state with respect to the collection of taxes, interest, additions to tax, and penalties. The agreements may provide, at the discretion of the board, the rate of payment and the manner in which compensation for services shall be paid. The compensation shall not be added to the amount required to be collected by the collection agency or provider of debt collection services from the tax debtor. The board shall provide the necessary information for the contractor to fulfill its obligation under the agreement.

(b) With the approval of the board, the contractor may, as part of the collection process, refer the tax debt for litigation by its legal representatives in the name of the board.