View all Attorneys
Williams Kastner Member

Tyler J. Hermsen

Tyler J. HermsenMember
Bar Admissions


U.S. District Court
Western District of Washington

Tyler J. Hermsen


Tyler Hermsen is a Member at the Seattle office of Williams Kastner and his practice focuses on preparing and trying cases; primarily in the areas of mass torts and commercial litigation.  Tyler is a courtroom litigator and has regularly found himself involved in some of the most substantial civil trial matters in Western Washington over the past decade.  He has represented hundreds of clients—from individuals to Fortune 50 companies most of which involved high stakes, multi-million dollar claims.  Tyler approaches each matter with a specific eye for the needs of the client in light of the uncertainty and complexity that comes with high leverage courtroom litigation; especially matters involving difficult facts for his clients.


Seattle University School of Law
J.D., 2008

University of Washington
B.A., 2004

Presentations & Seminars

Tyler has been invited to speak at CLE programs in the Seattle area on the topics of asbestos-defense trial strategy and trial preservation of error.

Representative Experience

Toxic Tort and Products Liability Litigation: Tyler’s experience in toxic tort litigation runs the entire gamut of the practice area on a local and national level; from case inception through appeal.  Tyler serves on trial teams for several asbestos defendant clients regionally and serves on National Coordinating Counsel teams.  He tried two to multi-week asbestos trials to verdict since the COVID-19 outbreak, including what is believed to be the first jury trial of any kind that was commenced in Washington following the shutdown.  Tyler has directed and defended some of the top defense experts and cross-examined some of the most frequent plaintiff’s experts in both depositions and on the stand at trial.   He also regularly defends corporate representative depositions nationally.

Commercial Litigation: Tyler’s experience with high stakes personal injury litigation causes him to be regularly involved in complex commercial, extracontractual, consumer protection and intellectual property litigation matters at the firm as well.  Tyler’s experience in personal injury litigation is well suited for complex commercial matters as his approach is to prepare every case for defense at trial in order to leverage favorable exit strategies.

Ride the Ducks September 24, 2015 Aurora Bridge Collision Litigation: Tyler was a member of the trial team representing Ride the Ducks International, LLC in defense of dozens of catastrophic injury and wrongful death claims stemming from the single largest mass casualty incident in Washington State history.  He served as second chair trial counsel in the four-month Dinh et al v. Ride the Ducks International, LLC et al jury trial involving over 40 plaintiffs and was also a member of the trial team in all other actions involving the incident, including a separate four-week jury trial.

Olympus America Duodenoscope Mass Infection Litigation: Lead the defense of a national medical device group purchasing organization (“GPO”), in a wrongful death action in Washington stemming from the Olympus duodenoscope product defect/mass infection litigation.  This complex case involved claims of product defect, medical malpractice, breach of contract, general negligence and Washington’s Consumer Protection Act.

Other: Tyler has tried several civil jury trials to verdict and conducted nearly one hundred arbitrations.  He represents clients in a variety of litigation areas, including: personal injury, construction defect, insurance coverage, insurance fraud, premises liability, medical malpractice, employment, subrogation, and motor vehicle tort.