Expert Witness Blog

Expert Witness Rules, Laws and Procedure in Washington

Washington Rules Regarding Expert Witness Depositions and Interrogatories 

Washington Civil Rule 26(b)(5)(A)(ii) allows a party to depose all experts its opponent expects to call at trial. Washington Rules do not specifically limit the time allowed for the taking of a deposition, but Rule 30(b)(3) states that a court may increase of decrease the allowed time for cause. Experts generally may not be subject to interrogatories in Washington, as they are only served on the parties. As discussed in the following section, though, these interrogatories can require disclosures about experts and, accordingly, expert participation in responding to certain interrogatories may be helpful. 

Washington Expert Witness Reports and Disclosures Rules 

The extent to which disclosures regarding experts are required in Washington depends on whether the expert is expected to testify at trial or has been retained solely for consulting purposes. For the latter category of experts, Washington Civil Rule 26(b)(5)(B) provides that discovery may only be had upon a showing of exceptional circumstances under which it is impracticable for the party seeking discovery to obtain facts or opinions on the same subject by other means. This is a difficult standard to meet, and it protects even the identities of consulting experts. See Detwiler v. Gall, 712 P.2d 316 (Wash Ct. App. 1986).

For an expert expected to be called at trial, Rule 26(b)(5)(A)(i) provides that a party can be required to disclose the identity of such expert, the subject matter on which he or she is expected to testify, the substance of the facts and opinions to which the expert is expected to testify, and a summary of the basis for these opinions upon interrogatory from the opposing party. Although there is no affirmative initial obligation to provide a testifying expert’s report to the opposing party, the Washington Supreme Court has confirmed that such written materials of testifying experts may be discovered by a formal request for a production of documents as part of the expert’s deposition. In re Det. of West, 256 P.3d 302, 314 (Wash. 2011) (note that although this proceeding was related to a criminal matter, the Court was interpreting Washington Civil Rule 26(b)(5)). Accordingly, it is normal practice in Washington to serve a request for the production of documents on the opposing party, seeking the expert’s report and supporting documents. LN Practice Guide: WA Civil Discovery § 9.03, Scope of Expert Witness Discovery (2014). 

Rules Regarding Lawyer-Expert Communications, Draft Expert Witness Reports, Expert Witness Notes, Etc. in Washington 

There is little guidance in Washington rules or cases regarding the discoverability of lawyer-expert communications, draft reports, and other preliminary materials. However, the Washington Practice Guide cited above makes clear that while the common practice of document production requests may not reach a testifying expert’s entire file, “it can extend to documents and communications exchanged between the party and the expert and documents supporting the expert’s report in the party’s possession.” Id.

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