Does Washington use the Daubert or Frye standard for expert witnesses?

Washington uses Frye. It is one of the minority of states that declined to follow the United States Supreme Court's decision in Daubert, and its courts continue to apply the general-acceptance test to novel scientific evidence: the theory and the technique must be generally accepted in the relevant scientific community before the resulting opinion reaches a jury. Daubert applies in the federal courts sitting in Washington, meaning the Western and Eastern Districts, which follow Federal Rule of Evidence 702 as amended in December 2023. The same case can therefore face two different admissibility tests depending on whether it stays in superior court or is removed.

What makes expert testimony admissible in Washington?

Two requirements, argued separately. If the opinion depends on novel scientific evidence, Frye asks whether the underlying theory and the method used to apply it are generally accepted in the relevant scientific community. Then ER 702 asks whether the witness is qualified by knowledge, skill, experience, training, or education, and whether the specialized knowledge offered will assist the trier of fact. Testimony that is speculative, or that addresses matters a jury can resolve without help, may be excluded under ER 702 even where the science is entirely conventional. Most expert testimony in Washington is analyzed under ER 702 alone, without a Frye hearing.

What governs expert disclosure in Washington?

There is no uniform statewide date. CR 26(b)(5) addresses the substance of what is disclosed through expert interrogatories — the identity of each expert expected to testify, the subject matter, the substance of the facts and opinions, and a summary of the grounds. The date itself comes from the court's case schedule or scheduling order in the individual case. King County Superior Court issues a case schedule at filing that addresses primary and rebuttal witness disclosure; other counties set their own practice. This site does not calculate any of those dates. Because they are county- and matter-specific, counsel must confirm them against the governing order rather than any general summary, including this one.

What does an expert witness cost in Washington?

Fees are hourly and vary by specialty, record volume, and whether the matter reaches deposition or trial. Physician and engineering experts commonly bill in the range of several hundred dollars per hour for record review and report preparation, with higher rates for testimony, which is often subject to a half-day or full-day minimum. Financial and valuation work is usually quoted against the scope of the analysis. Preliminary screening is at no charge, and a written fee schedule issues before any engagement begins. Deposition time is ordinarily paid by the party taking the deposition, subject to the applicable rule and any order in the case.

Can an expert witness testify remotely in Washington?

Remote deposition testimony is routine in Washington state and federal courts, and remote or hybrid trial testimony is available in many courtrooms subject to the judge's discretion, the applicable rules, and any standing order. Practices vary between King, Pierce, Snohomish, and Spokane counties and between the Western and Eastern Districts, so the specific requirement should be confirmed with the assigned department. Remote appearance materially reduces the travel component of expert cost, which matters most in matters east of the Cascades and in cases where the technical issue is significant but the exposure does not justify multi-day travel.

How do I find an expert witness in Washington state?

Start with the admissibility standard rather than the credential list, because a Washington engagement is a Frye engagement. The questions worth asking early are whether the method the expert intends to use is generally accepted in the field, whether the expert has testified under Washington's standard before, and whether the report can be produced within the disclosure date in the governing case schedule. Themis Expert Witness, LLC sources and vets experts against those criteria across medical, financial, forensic, and technical disciplines, and Dr. Alban remains involved through report review and trial preparation on every placement.

Where we serve

Expert Witness Services in Washington State

Washington is one of the minority of states that never adopted Daubert. Its courts screen novel scientific evidence under the Frye general-acceptance test, then apply ER 702 to the witness and the testimony, which makes admissibility planning here different from federal practice. Themis Expert Witness, LLC supplies medical, financial, forensic, and technical experts to plaintiff and defense counsel in Washington state and federal courts.

Does Washington follow Daubert or Frye?

Washington remains a Frye state. Novel scientific evidence is admissible only if the underlying theory and methodology are generally accepted in the relevant scientific community, and ER 702 then asks whether the witness qualifies as an expert and whether the testimony will help the trier of fact. Daubert does not govern Washington state courts.

The two inquiries do different work and are argued separately. Frye is directed at the science, not the scientist. It asks whether the theory the opinion rests on, and the technique used to apply it, have achieved general acceptance among qualified members of the field. The court is not weighing the persuasiveness of the method; it asks whether the scientific community has settled the question. Disagreement at the margins is tolerated. A live dispute over validity within the discipline is not.

ER 702 is the second gate. If a witness is qualified by knowledge, skill, experience, training, or education, and if scientific, technical, or other specialized knowledge will assist the trier of fact, the witness may testify in the form of an opinion. Washington courts read the helpfulness requirement to carry real content: testimony that is too speculative to assist, or that addresses matters the jury can resolve on its own, may be excluded even where nothing about the science is novel.

Frye applies to novel scientific evidence, not to every expert who takes the stand. Testimony grounded in ordinary clinical judgment, established engineering practice, or accepted accounting methodology is generally analyzed under ER 702 alone, without a Frye hearing. The threshold question is therefore whether the opinion depends on a theory or technique genuinely new to the courts, or on a novel application of an accepted method.

The practical consequence most often catches out-of-state counsel. Daubert's reliability inquiry is flexible and non-exclusive: a federal judge may admit a method that is peer-reviewed, testable, and carries a known error rate even if the wider field has not converged on it. Frye has no such flexibility. An opinion built on an emerging methodology can survive a federal Rule 702 challenge and still fail in a Washington superior court, because general acceptance is a threshold the method either clears or does not. Counsel who assume a report that held up federally transfers intact to King County are working from the wrong test.

The contrast matters within Washington itself. The federal courts for the Western and Eastern Districts of Washington apply Federal Rule of Evidence 702 and the Daubert line, including the December 2023 amendment making explicit the proponent's burden to establish admissibility by a preponderance. A case filed in Spokane County Superior Court and the same case removed to E.D. Wash. are governed by different standards, and reports are drafted accordingly rather than adapted after a challenge is filed.

Expert disclosure runs on the case schedule, not a statewide deadline

Washington has no single statewide expert disclosure deadline. CR 26(b)(5) governs the substance of what must be produced — through interrogatories, a party must identify each person expected to be called as an expert at trial, the subject matter of the expected testimony, and the substance of the facts and opinions plus a summary of the grounds for each opinion. What CR 26 does not supply is the date; that comes from the court's case schedule or scheduling order in the particular matter.

King County Superior Court is the familiar example. Under its local rules, a case schedule issues at filing and fixes dates for disclosure of possible primary witnesses and of additional or rebuttal witnesses, along with discovery cutoff and trial. Pierce, Snohomish, and Spokane counties operate their own case-setting practices, and individual departments add requirements of their own. These dates are county- and matter-specific; counsel should confirm each one against the governing order rather than any general description of Washington practice, including this one.

Washington authority addresses the consequences of late disclosure. Burnet v. Spokane Ambulance addresses the findings a trial court is expected to make on the record before imposing the harshest discovery sanctions — whether the violation was willful, whether it substantially prejudiced the opposing party's ability to prepare for trial, and whether a lesser sanction would suffice. That framework is general background; how it would be applied to any particular disclosure is a matter for the court and for counsel's judgment. The practical point from an expert's side is simply that early retention leaves more room in the schedule.

Courts served across Washington

Engagements run through the state superior courts that handle the bulk of Washington civil and criminal litigation — King County Superior Court in Seattle and Kent, Pierce County in Tacoma, Snohomish County in Everett, and Spokane County — and through the federal courts, the Western District of Washington in Seattle and Tacoma and the Eastern District in Spokane, Richland, and Yakima. Appeals from those federal matters go to the Ninth Circuit.

The split is not merely geographic: it determines the admissibility standard, the disclosure mechanism, and the shape of the report. A federal expert report under FRCP 26(a)(2)(B) is a signed, self-contained document stating the opinions, the facts considered, exhibits, qualifications, prior testimony, and compensation. A CR 26(b)(5) answer is a different instrument at a different level of detail. Preparing one and serving the other is a recurring source of avoidable motion practice.

Washington-specific areas where expert opinion decides the case

Medical negligence claims are addressed by RCW 7.70, which sets out the elements of such a claim, and Washington case law addresses the circumstances in which expert testimony is needed to establish the standard of care and its breach. RCW 7.70.150 was Washington's certificate-of-merit statute, requiring a supporting expert declaration at filing, until the Washington Supreme Court held it unconstitutional in Putman v. Wenatchee Valley Medical Center in 2009. Whether expert testimony is legally required in any particular matter — and what the current law requires — is a determination for counsel, not one this site makes. As a practical matter, most medical negligence work that reaches us involves standard-of-care and causation opinion.

Insurance disputes are the second recurring area. The Insurance Fair Conduct Act, RCW 48.30.015, is the statute addressing a first-party claimant's remedies where coverage or payment has been unreasonably denied, including the enhanced damages and fees a court may award. Whether it applies to any given claim is a question for counsel. IFCA and bad-faith claims commonly turn on claims-handling custom and practice and the reasonableness of the coverage position taken, which is the ground an insurance expert who has worked inside the industry is retained to cover.

Construction defect litigation is a durable Washington practice area, driven by the region's rain-driven envelope failures and its seismic requirements, and it usually needs architectural, structural, and cost experts working the same record. Workplace injury and safety claims add another category: Washington administers its own occupational safety program through the Division of Occupational Safety and Health within the Department of Labor and Industries, under WISHA and RCW 49.17, so a safety opinion framed only around federal OSHA standards can miss the regulation actually cited.

Specialties available through the network

Themis Expert Witness, LLC operates as a managed expert network. Dr. Alvaro Alban, MD, MBA — board certified in emergency medicine, with over twenty years of expert witness experience across more than 150 cases — personally handles emergency medicine and medical causation. For every other discipline he identifies, vets, and manages an independently credentialed expert, then stays involved through report review and trial preparation.

Available specialties include medical standard of care and causation, forensic pathology, toxicology, forensic psychology, financial and economic damages, forensic accounting, business valuation, real estate appraisal, vocational and life-care analysis, insurance claims practice, architectural and structural engineering, and construction site safety. Where a matter has both a technical and a medical dimension — a fall from height, a chemical exposure — the disciplines are coordinated so the opinions align rather than contradict one another on cross.

How an engagement begins

The first step is a preliminary screening call at no charge. Counsel describes the claim, the venue, and the schedule; the discussion covers which expert discipline the issue points to, what records exist, availability and conflicts, and whether the materials look suitable for expert review. Where they do not, counsel is told during that call rather than after a deposition has exposed the problem. Screening does not include legal analysis, evaluation of claims or defenses, calculation of deadlines, or any view on whether a lawsuit is viable.

If the matter proceeds, a written fee schedule issues before any work begins. Review, report preparation, deposition, and trial testimony are billed separately at stated hourly rates, and testimony days are commonly subject to a half-day or full-day minimum. Nothing here is legal advice and no outcome is predicted. Deadlines, disclosure obligations, and admissibility rulings are matter-specific, and retaining counsel remains responsible for confirming them against the governing order.

Courts and venues served in Washington

Reports, depositions, and trial testimony are provided in Washington state and federal courts — in person in Seattle, Tacoma, Everett, and Spokane, and remotely where the court permits. The venues below account for most Washington engagements:

State courts

King County Superior Court
Pierce County Superior Court
Snohomish County Superior Court
Spokane County Superior Court

Federal districts

W.D. Wash.
E.D. Wash.

Federal matters in Washington are governed by Federal Rule of Evidence 702 and the Daubert line of authority, not by the state standard described above.

Specialties available in Washington

Medical Expert Witness Financial Expert Witness Forensic Psychologist Expert Witness Toxicology Expert Witness Forensic Pathologist Expert Witness Insurance Expert Witness Real Estate Appraisal Expert Witness Vocational Economist Expert Witness Forensic Accountant Expert Witness Business Valuation Expert Witness Architectural Expert Witness Construction Site Safety Expert Witness Structural Engineer Expert Witness

Frequently Asked Questions

: Washington uses Frye. It is one of the minority of states that declined to follow the United States Supreme Court's decision in Daubert, and its courts continue to apply the general-acceptance test to novel scientific evidence: the theory and the technique must be generally accepted in the relevant scientific community before the resulting opinion reaches a jury. Daubert applies in the federal courts sitting in Washington, meaning the Western and Eastern Districts, which follow Federal Rule of Evidence 702 as amended in December 2023. The same case can therefore face two different admissibility tests depending on whether it stays in superior court or is removed.
: Two requirements, argued separately. If the opinion depends on novel scientific evidence, Frye asks whether the underlying theory and the method used to apply it are generally accepted in the relevant scientific community. Then ER 702 asks whether the witness is qualified by knowledge, skill, experience, training, or education, and whether the specialized knowledge offered will assist the trier of fact. Testimony that is speculative, or that addresses matters a jury can resolve without help, may be excluded under ER 702 even where the science is entirely conventional. Most expert testimony in Washington is analyzed under ER 702 alone, without a Frye hearing.
: There is no uniform statewide date. CR 26(b)(5) addresses the substance of what is disclosed through expert interrogatories — the identity of each expert expected to testify, the subject matter, the substance of the facts and opinions, and a summary of the grounds. The date itself comes from the court's case schedule or scheduling order in the individual case. King County Superior Court issues a case schedule at filing that addresses primary and rebuttal witness disclosure; other counties set their own practice. This site does not calculate any of those dates. Because they are county- and matter-specific, counsel must confirm them against the governing order rather than any general summary, including this one.
: Fees are hourly and vary by specialty, record volume, and whether the matter reaches deposition or trial. Physician and engineering experts commonly bill in the range of several hundred dollars per hour for record review and report preparation, with higher rates for testimony, which is often subject to a half-day or full-day minimum. Financial and valuation work is usually quoted against the scope of the analysis. Preliminary screening is at no charge, and a written fee schedule issues before any engagement begins. Deposition time is ordinarily paid by the party taking the deposition, subject to the applicable rule and any order in the case.
: Remote deposition testimony is routine in Washington state and federal courts, and remote or hybrid trial testimony is available in many courtrooms subject to the judge's discretion, the applicable rules, and any standing order. Practices vary between King, Pierce, Snohomish, and Spokane counties and between the Western and Eastern Districts, so the specific requirement should be confirmed with the assigned department. Remote appearance materially reduces the travel component of expert cost, which matters most in matters east of the Cascades and in cases where the technical issue is significant but the exposure does not justify multi-day travel.
: Start with the admissibility standard rather than the credential list, because a Washington engagement is a Frye engagement. The questions worth asking early are whether the method the expert intends to use is generally accepted in the field, whether the expert has testified under Washington's standard before, and whether the report can be produced within the disclosure date in the governing case schedule. Themis Expert Witness, LLC sources and vets experts against those criteria across medical, financial, forensic, and technical disciplines, and Dr. Alban remains involved through report review and trial preparation on every placement.

Also serving

California Expert Witness Services

California applies the Sargon standard to expert testimony.

Oregon Expert Witness Services

Oregon applies the Brown/O'Key standard to expert testimony.

Complimentary preliminary screening

Retain an expert witness in Washington

Send the posture of your Washington matter — court, claims, and the schedule you are working under — and you will get a candid read on which expert discipline the issue points to and whether the materials look suitable for expert review. Preliminary screening does not include legal analysis or calculation of any deadline. Serving attorneys and law firms throughout California, Washington, and Oregon — available for consultation, report preparation, deposition, and trial testimony, in person and remotely.

Service area: California, Washington, and Oregon — state and federal courts, in person and by remote deposition.
Phone: (347) 860-4763
Email: office@themisexpertwitness.com

Full name *

Law firm / organization

Email *

Phone

Specialty needed

Venue / jurisdiction

Brief description of the matter *

Please do not include privileged or confidential client information in this initial message.

I understand that West Coast Expert Witness and Themis Expert Witness, LLC are not law firms, do not provide legal advice or representation, and are not responsible for determining legal claims, procedural requirements, or deadlines. *

Submission of this form does not create an attorney-client relationship, expert-retention relationship, fiduciary relationship, or confidential relationship. West Coast Expert Witness and Themis Expert Witness, LLC do not provide legal advice and are not responsible for identifying, calculating, or preserving litigation deadlines.

Complimentary preliminary screening is limited to identifying a potentially appropriate expert discipline, checking availability and conflicts, and determining whether the submitted materials may be suitable for expert review. It does not include legal analysis, evaluation of claims or defenses, calculation of deadlines, or an opinion concerning whether a lawsuit is viable.

If you are not represented by an attorney: Individuals without counsel should consult a licensed attorney regarding the viability of their claims and all applicable deadlines before retaining an expert.