Background
In December 2019, Shawn and Tanya Maywald were struck head-on by a northbound driver who fell asleep and drifted across the center line on State Route 77. Shawn suffered major injuries. The Maywalds sued Toyota Motor Corporation, Toyota Motor North America, Inc., and the dealership Overtyme, Inc., asserting strict liability for design defect, negligent design, and loss of consortium. Their sole alleged defect: the 2019 Toyota 4Runner was not equipped with a lane departure warning (LDW) system—technology that alerts drivers when their vehicle drifts from a lane—which Toyota did not offer as a standard or optional feature on that model year.
Toyota moved for summary judgment, arguing the 4Runner was neither defective nor unreasonably dangerous and that the lack of LDW did not cause the accident. The Navajo County Superior Court granted Toyota’s motion and entered final judgment in its favor. The court of appeals vacated that ruling, applying the risk/benefit analysis and concluding that genuine issues of material fact existed as to whether the benefits of including LDW outweighed the risks of omitting it. The court of appeals also found triable issues on negligent design and proximate causation.
The Arizona Supreme Court granted Toyota’s petition for review to resolve two recurring questions of statewide importance: whether strict product liability requires independently establishing both defect and unreasonable danger, and how the consumer expectation test and risk/benefit analysis properly apply within that framework.
The Court’s Holding
The court vacated the court of appeals’ decision and reinstated the trial court’s summary judgment for Toyota. Writing for a unanimous court, Justice Beene reaffirmed Arizona’s two-element strict liability standard: a plaintiff must prove (1) the product was sold in a defective condition, and (2) the defect rendered the product unreasonably dangerous. The court disapproved prior court of appeals decisions—Dillon v. Zeneca Corp., Golonka v. General Motors Corp., and Gomulka v. Yavapai Machine & Auto Parts—to the extent those cases collapsed the two elements into one, and it also disapproved any language in Dart v. Wiebe Manufacturing that blurred the distinction.
On the facts, the court held that the absence of an LDW system did not place the 4Runner in a defective condition. A product is defective when it is unsafe for normal handling and consumption—a condition not reasonably contemplated by the ordinary consumer that renders the product unfit for intended use. Because ordinary vehicle operation requires an attentive driver to steer and remain in the proper lane, the court reasoned that a vehicle without LDW technology is not unsafe for normal use; a driver asleep at the wheel is not engaged in normal use of the vehicle. The court found the reasoning of the New Jersey Appellate Division in Berkoski v. Honda Motor Co. persuasive and directly on point.
The court also clarified that the risk/benefit analysis must focus on the risks and benefits inherent in the challenged design itself—the 4Runner without LDW—not on a comparative weighing of an alternative design that incorporates LDW. The court warned that reorienting the inquiry around alternative designs would effectively require manufacturers to incorporate every feasible safety feature or face liability, potentially rendering products prohibitively expensive. Because the Maywalds failed to establish the threshold element of defect, the court did not reach the unreasonable danger prong, but addressed the risk/benefit issue to correct the analytical error below. With no viable underlying tort claim, the negligent design and loss of consortium claims failed as well.
Key Takeaways
- Arizona strict product liability requires two independent showings: (1) the product was defective and (2) the defect rendered it unreasonably dangerous. Failing on defect ends the analysis entirely.
- The absence of an available driver-assistance feature—such as lane departure warning—does not by itself render a vehicle defective under Arizona law; ordinary vehicle use presupposes an attentive driver, not one asleep at the wheel.
- The risk/benefit analysis must be applied to the challenged design as sold, not to a comparison between the challenged design and a hypothetical alternative design incorporating omitted safety features.
- Dillon, Golonka, and Gomulka are disapproved to the extent they merged defectiveness and unreasonable danger into a single inquiry.
- Negligent design and loss of consortium claims both require the same threshold showing of product defect; if defect is not established, both derivative claims fail with the strict liability claim.
Why It Matters
This decision provides significant clarity—and protection—for vehicle manufacturers in Arizona by confirming that the failure to include an available but optional driver-assistance technology does not expose a manufacturer to strict liability or negligence liability as a design defect. Plaintiffs must clear a genuine defect threshold before any analysis of unreasonable danger even begins. The ruling forecloses a litigation theory that, if accepted, could have compelled manufacturers to equip every vehicle with every technologically feasible safety system or face potential liability for omissions.
More broadly, the decision restores a clear two-step analytical framework that had been eroding through inconsistent intermediate appellate decisions for decades. By expressly disapproving Dillon, Golonka, and Gomulka and correcting the court of appeals’ misapplication of the risk/benefit analysis, the Arizona Supreme Court draws a firm doctrinal line between strict liability and absolute liability—a distinction that shapes defense strategy, expert witness requirements, and summary judgment practice in every Arizona product liability case going forward.