California Code, Family Code - FAM § 5230.1

(a) An earnings assignment or income withholding order for support issued by a court or administrative agency of another state is binding upon an employer of the obligor to the same extent as an earnings assignment order made by a court of this state.

(b) When an employer receives an earnings assignment order or an income withholding order for support from a court or administrative agency in another state, all of the provisions of this chapter shall apply.