California Expert Witness Discovery Rules

What Is the Scope of Expert Discovery in California?

The scope of expert discovery in California is delineated by specific statutory provisions rather than mirroring the Federal Rule of Civil Procedure 26(b)(4). Under California law, expert discovery is governed by the California Code of Civil Procedure, particularly sections 2034.210 through 2034.310. These rules outline the permissible discovery of expert information, including the designation of expert witnesses, the exchange of expert witness information, and the deposition of such experts.

• California does not permit the discovery of draft reports or attorney–expert communications, with certain exceptions for materials that demonstrate bias or are factual in nature.
• The state's framework focuses heavily on the formal exchange of expert information, ensuring that all parties have a clear understanding of the expert testimony expected at trial.

Timing and Procedure for Expert Discovery in California

Expert discovery in California follows a structured timetable, notably distinct from rolling discovery practices. According to CCP Section 2034.210–2034.270, parties must engage in a mutual exchange of expert witness information approximately 50 days before trial. This exchange is triggered by a party's demand and necessitates simultaneous service of expert designations by all involved parties.

• Each party must submit an expert designation identifying the expert by name and address, accompanied by a brief narrative of the expected testimony.
• For retained experts, a declaration must affirm the expert's availability and the general substance of their opinions.
• A supplemental (rebuttal) disclosure is permitted 20 days after the initial exchange, allowing parties to address new matters introduced by opposing experts.

What Methods of Expert Discovery Are Permitted in California?

California permits several methods of expert discovery, including depositions and document requests. Retained experts, specially engaged for litigation, can be deposed as a matter of right (Cal. Code Civ. Proc. § 2034.310). The opposing party may also demand production of the expert’s writings and reports.

• Non-retained experts, such as treating physicians, must be listed but are not required to provide written reports.
• The discovery process in California is specifically designed to focus on testifying experts, with consulting expert materials generally protected unless exceptional circumstances warrant disclosure.

Limits on Discovery of Expert Materials and Communications

California imposes specific limits on the discovery of expert materials and communications. While draft reports and attorney–expert communications are typically shielded from discovery, certain exceptions apply:

• Discovery may extend to materials demonstrating potential bias or reflecting facts and data considered by the expert in forming their opinions.
• Compensation details are generally discoverable, especially if relevant to assessing the expert's potential bias.

California courts have developed a body of case law interpreting these rules, often deviating from federal standards by placing a greater emphasis on the protection of attorney–expert communications.

Consequences for Noncompliance or Discovery Violations

Failure to comply with California's expert discovery rules can result in significant consequences. Under CCP Section 2034.280, non-disclosure or failure to serve a compliant expert designation or report by the deadline may lead to the exclusion of the expert's testimony at trial.

• Sanctions for discovery violations can include exclusion of evidence, continuances, or monetary penalties.
• Courts strictly enforce these rules to ensure fair and efficient trial preparation, emphasizing the importance of timely and complete expert disclosures.

Relevant Rules and Legal Authority in California

The California Code of Civil Procedure serves as the primary legal authority governing expert discovery. Key sections include:

• **Cal. Code Civ. Proc. §§ 2034.210–2034.280**: Detailing the mutual exchange of expert information.
• Cal. Code Civ. Proc. § 2034.300: Addressing the exclusion of experts for non-compliance.
• Cal. Code Civ. Proc. § 2034.310: Permitting the deposition of retained experts.

These provisions highlight California's distinct approach to expert discovery, emphasizing formal exchanges and adherence to strict procedural timelines, in contrast to the federal model.