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Williams Kastner Member

Tyler J. Hermsen

Tyler J. HermsenMember
Bar Admissions

U.S. District Court
Western Washington


Tyler J. Hermsen


Tyler Hermsen is Of Counsel at the Seattle office of Williams Kastner and his practice focuses on products liability, mass torts and litigation.  Tyler is a litigator and has extensive experience as a trial lawyer and in all phases of civil litigation, including discovery, motion practice, trials/arbitrations, and appeals.  He has represented hundreds of individuals, professionals and corporate entities—from individuals to Fortune 50 companies—as lead counsel and taken several civil jury trials to verdict across Washington.

Tyler has a varied background and has represented clients in complex civil matters involving product liability, wrongful death and catastrophic injury, premises and construction liability, insurance defense and insurance fraud, commercial litigation, and medical malpractice. Tyler approaches each matter with a specific eye for the needs of the client in light of the uncertainty and complexity that comes with civil jury trial litigation.


Seattle University School of Law
J.D., 2008

University of Washington
B.A., 2004

Representative Experience

Ride the Ducks September 24, 2015 Aurora Bridge Collision Litigation: Member of the trial team representing Ride the Ducks International, LLC in defense of dozens of product liability claims involving catastrophic injury and wrongful death stemming from the largest “mass casualty incident” in Washington State history.  On September 24, 2015 a DUKW amphibious vehicle manufactured by RTDI filled with tourists crossed the centerline on the Aurora Bridge in Seattle and collided with a motor coach carrying international students from North Seattle College.  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. This extremely difficult liability case with undisputed catastrophic injuries resulted in a verdict of just 1/3 of the amount demanded by the plaintiffs.  He 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.  Leveraged favorable dismissal and release of client prior to trial (terms confidential).

Other Representative Experience

Civil Jury Trials: Tyler is a seasoned civil trial attorney.  He has served as lead defense counsel on several civil personal injury jury trials across Washington involving a wide variety of claims and issues, some of which are referenced below.

Complex Civil Litigation: Tyler has been a member of several trial teams involving mass tort claims outside the products liability arena in the areas of personal injury, property damage/fire, and sex abuse litigation involving youth, religious and charitable organizations, as well as complex commercial matters including construction defect litigation.

Insurance Fraud Investigations: Tyler has extensive experience investigating false claims and medical provider insurance fraud.  His experience spans examinations under oath to jury trials involving fraudulent medical providers.  Matters involved false claim reporting, treatment billed and not rendered, illegal attorney-provider and provider-provider kick-back schemes, civil RICO, Stark Law issues, and corporate practice of medicine.  Many medical providers and attorneys simply chose to “walk away” from clients and patients in third-party tort actions involving Tyler’s investigations in order to avoid cross examination and further scrutiny.

Represented client in a two week jury trial involving catastrophic spinal injuries stemming from a motor vehicle collision.  The teenage plaintiff underwent a spinal surgery following the collision and claimed permanent injuries.  Verdict against client totaled $4,350.00, which was significantly less than settlement offers and less than the costs awarded to client pursuant to CR 60.

Represented client in a jury trial stemming from car versus pedestrian collision involving catastrophic injuries to knee, including claim for knee future replacement.  Defense verdict.

Represented clients in two separate personal injury jury trials involving admitted liability where verdict included nominal general damages awards and successfully defended motions for additur following verdict.

Represented clients in admitted liability personal injury jury trials where significant portions of medical special damages were not awarded to the plaintiff based on Tyler’s fraud investigations and argument.

Represented a chiropractor that was the football team medical assistant in a medical malpractice action.  Plaintiff was a star football player that suffered multiple catastrophic brain injuries during games, unbeknownst to client who was not present, nor was told about the injuries by anyone, including his coaches.  Leveraged a complete release and dismissal prior to trial on favorable terms (confidential).

Represented real estate holding company in a negligence and premises liability claim involving undisputed catastrophic injuries with resultant permanent disability.  Argued successful motion for summary judgment based on the retained control and judicial estoppel doctrines.

Represented a big box retailer in a premises liability action involving alleged violations of the Americans with Disabilities Act.   Argued successful motion for summary judgment.

Represented a tribal casino client in a premises liability action and argued successful motion for summary judgment.

Represented a specialty automotive retailer client as second chair in a nine-day jury trial involving claims for breach of contract and violations of Washington’s Consumer Protection Act and Automotive Repair Act.  Settled the evening before closing arguments for just 10% of pretrial demand.