California Code, Code of Civil Procedure - CCP § 1258.020

(a) Notwithstanding any other statute or any court rule relating to discovery, proceedings pursuant to subdivision (b) may be had without requirement of court order and may proceed until not later than 20 days prior to the day set for trial of the issue of compensation.

(b) A party to an exchange of lists of expert witnesses and statements of valuation data pursuant to Article 2 (commencing with Section 1258.210) or pursuant to court rule as provided in Section 1258.300 may after the time of the exchange obtain discovery from the other party to the exchange and from any person listed by him as an expert witness.

(c) The court, upon noticed motion by the person subjected to discovery pursuant to subdivision (b), may make any order that justice requires to protect such person from annoyance, embarrassment, or oppression.