Missouri Expert Witness Discovery Rules

What Is the Scope of Expert Discovery in Missouri?

In Missouri, the scope of expert discovery is defined under Missouri Supreme Court Rule 56.01, which governs the discovery of expert information. Unlike the federal system, Missouri adheres to its own procedural framework, although there are similarities to Federal Rule of Civil Procedure 26(b)(4). Missouri requires parties to disclose expert witnesses and details of their testimony according to a court-directed schedule, typically following Rule 56.01. This rule permits interrogatories asking for the identity of each expert a party expects to call, the subject matter of their testimony, their conclusions and opinions, and the basis for those opinions. Additionally, the expert's qualifications and any prepared reports must be disclosed. However, limits exist regarding the discovery of draft reports and communications between attorneys and experts to protect work-product and privilege considerations.

Timing and Procedure for Expert Discovery in Missouri

Expert discovery in Missouri generally occurs after initial disclosures, in line with a court-directed schedule. Missouri trial courts frequently issue scheduling orders setting deadlines for expert disclosures, often staggered for plaintiffs and defendants, and may require the exchange of written expert reports. If an expert report exists, it should be produced, otherwise, the interrogatory response serves as a summary of the expert's opinions. The procedural steps include serving interrogatories under Rule 56.01, disclosing expert information, and taking depositions once an expert is disclosed. Missouri Supreme Court Rule 56.01(e) mandates the supplementation of expert discovery responses if there are material changes.

What Methods of Expert Discovery Are Permitted in Missouri?

In Missouri, the methods of expert discovery permitted include:

• Interrogatories: Parties can serve interrogatories asking for detailed expert information, such as opinions, bases, and qualifications.
• Depositions: Once an expert is disclosed, parties may depose the expert to explore their opinions and bases in detail.

Discovery primarily focuses on testifying experts, although non-retained experts, like treating physicians, are also subject to disclosure. However, they are not required to provide written reports, instead, their opinions are summarized in the interrogatory answer. Consulting experts remain protected unless exceptional circumstances arise.

Limits on Discovery of Expert Materials and Communications

Missouri places certain limits on the discovery of expert materials and communications. Draft reports, attorney-expert communications, and compensation details are generally protected. However, exceptions exist, such as when bias, reliance materials, or facts/data considered by the expert are involved. Missouri courts have not significantly deviated from these protections, aligning closely with federal standards, albeit without the explicit adoption of the 2010 federal amendments to Rule 26(b)(4).

Consequences for Noncompliance or Discovery Violations

Failure to comply with expert discovery rules can lead to significant consequences under Missouri Rule 61.01. Sanctions may include the exclusion of the expert's testimony, monetary penalties, or continuances. Courts enforce these rules to ensure fairness and adherence to procedural requirements, emphasizing the importance of timely and complete disclosures.

Relevant Rules and Legal Authority in Missouri

Missouri's expert discovery is governed by several key rules and statutes:

• [Mo. Sup. Ct. R. 56.01](https://www.courts.mo.gov/page.jsp?id=199668): Governs expert interrogatories and the duty to supplement discovery responses.
• Mo. Sup. Ct. R. 61.01: Details sanctions for discovery violations.
• § 490.065 RSMo: Outlines the standard for expert admissibility, adhering to the Frye standard.

While Missouri's rules share some similarities with federal practices, they maintain distinct procedures and standards, particularly in the treatment of expert materials and communications. For more information, you can explore the Missouri Rules of Civil Procedure.