From the Courts’ and Legislature’s perspective, the purpose of discovery is to exchange information between the parties so each side can evaluate their strengths and weaknesses of their case, so that they are able to resolve the case or, if settlement is not possible, to safeguard against surprise at trial to avoid unnecessary delays and appeals.  From the parties’ perspective, the purpose is to obtain as much as you need from your opponent about their case.  Most critical to this process is taking the depositions of opposing parties’ experts. However, in order to have the right to take those depositions, you must strictly follow the rules for expert witnesses outlined in Code of Civil Procedure section 2034.010 et seq., starting with the demand for simultaneous exchange of expert trial witness information pursuant to CCP § 2034.210 titled “Demand for simultaneous exchange of expert trial witness information; List; Expert witness declaration; Discoverable reports and writings”, which reads:

After the setting of the initial trial date for the action, any party may obtain discovery by demanding that all parties simultaneously exchange information concerning each other’s expert trial witnesses to the following extent:

(a) Any party may demand a mutual and simultaneous exchange by all parties of a list containing the name and address of any natural person, including one who is a party, whose oral or deposition testimony in the form of an expert opinion any party expects to offer in evidence at the trial. 

(b) If any expert designated by a party under subdivision (a) is a party or an employee of a party, or has been retained by a party for the purpose of forming and expressing an opinion in anticipation of the litigation or in preparation for the trial of the action, the designation of that witness shall include or be accompanied by an expert witness declaration under Section 2034.260.

(c) Any party may also include a demand for the mutual and simultaneous production for inspection and copying of all discoverable reports and writings, if any, made by any expert described in subdivision (b) in the course of preparing that expert’s opinion.

Time for making demand

Code of Civil Procedure §2034.220 titled “Leave of court not required; Time for making demand” states: 

Any party may make a demand for an exchange of information concerning expert trial witnesses without leave of court. A party shall make this demand no later than the 10th day after the initial trial date has been set, or 70 days before that trial date, whichever is closer to the trial date.

If that day falls on a Saturday, Sunday, or court holiday, the last day to make your demand is the next court day closer to the trial date.  CCP §2034.220

A new trial date does not extend the time to make a demand for the exchange of expert witness information. You must request the trial court to change discovery cut off dates or reopen discovery if you want a new exchange date for expert disclosure.  However, this is not the case when a trial date is set after a mistrial, order granting a new trial, or reversal on appeal.  See Cal. Civil Discovery Practice (CEB 2020, Fourth Ed.)  §11.10-11.

HINT:  Rather than waiting until the last minute and potentially losing your right to obtain expert disclosures from the other side, demanding expert disclosure as soon as the case is set for trial avoids the problem. This way you never have to worry about missing the deadline.

Form and Content of Demand

The demand must comply with CCP §2034.230 titled “Form and content of demand for exchange of expert witness information” which states:

(a) A demand for an exchange of information concerning expert trial witnesses shall be in writing and shall identify, below the title of the case, the party making the demand. The demand shall state that it is being made under this chapter.

(b) The demand shall specify the date for the exchange of lists of expert trial witnesses, expert witness declarations, and any demanded production of writings. The specified date of exchange shall be 50 days before the initial trial date, or 20 days after service of the demand, whichever is closer to the trial date, unless the court, on motion and a showing of good cause, orders an earlier or later date of exchange.

HINT:  If the case is expert driven or more than five expert depositions per side are going to be taken, consider moving the expert disclosure from 50 days before trial to 75, 90, or even 150 days before trial. This can be done either by stipulation or bringing a motion for protective order pursuant to CCP §2034.250(b)(2).

You can find a form for the Demand for Exchange of Expert Trial Witness Information at Cal. Civil Discovery Practice (CEB 2020, Fourth Ed.) §11.69

Serving the Demand 

According to CCP §2034.240 titled “Service of demand”,

The party demanding an exchange of information concerning expert trial witnesses shall serve the demand on all parties who have appeared in the action

REMEMBER.  If there is no timely demand, the statutory procedure for exchange is optional.  See Cal. Civil Discovery Practice (CEB 2020, Fourth Ed.) §11.09 citing Perry v. Bakewell Hawthorne, LLC (2017) 2 C5th 536, 543.