Arizona Supreme Court Clarifies Product Liability Standard

Maywald v. Toyota Motor Corp., No. CV-25-0009-PR

Supreme Court of Arizona

July 7, 2026

JSH Attorneys: Elizabeth B.N. Garcia, Anton Sorkin

Arizona Supreme Court Reaffirms That Strict Product Liability Requires Independent Proof of Both a Defect and Unreasonable Danger, and Clarifies That the Risk/Benefit Analysis Looks Only to the Challenged Design

Yesterday, the Arizona Supreme Court clarified the elements of a strict products liability claim and the proper application of the risk/benefit analysis to a design defect claim based on the failure to equip a vehicle with Lane Departure Warning technology. The Court held that the risk/benefits analysis focuses on the risks and benefits inherent in the challenged design alone and not on a direct comparison with an alternative design, although evidence concerning an alternative design may inform the inquiry.

In 2019, Shawn and Tanya Maywald were injured when the driver of a Toyota 4Runner fell asleep, crossed the center line, and struck their vehicle head-on. The Maywalds brought strict liability design defect, negligent design, and loss of consortium claims, alleging that the 4Runner was defective and unreasonably dangerous because it did not include a lane departure warning (“LDW”) system—technology that alerts a driver who drifts out of their lane. The LDW technology was neither a standard nor optional feature on the 4Runner.

Toyota moved for summary judgment, arguing the 4Runner was not defective or unreasonably dangerous and that its design did not cause the accident. The Maywalds filed cross-motions for partial summary judgment on comparative fault and on how the risk/benefit analysis should apply to the 4Runner’s design. The superior court granted Toyota’s motions and denied the Maywalds’ motions. The court of appeals vacated that ruling, holding that the consumer expectation test did not apply because LDW was not a sufficiently well known or widely adopted feature. The court of appeals also found that the risk/benefit analysis applied, but concluded that it was not predicated on a threshold showing that the 4Runner was defective.  It instead reasoned that under the risk/benefit analysis, the court was not restricted to assessing the challenged design and instead had to weigh the risks of excluding LDW against the benefits of including it.  Applying this analysis, the court concluded that genuine disputes of material fact precluded summary judgment on the Maywalds’ strict liability, negligent design, and loss of consortium claims.

The Arizona Supreme Court granted review to resolve whether a strict product liability claim requires independent proof that a product is both defective and unreasonably dangerous, and to clarify the proper application of the consumer expectation test and risk/benefit analysis.

The Court first held that a plaintiff asserting a strict product liability claim under Arizona law must prove that the product was defective, and that the defect rendered it unreasonably dangerous.  The Court disapproved prior appellate decisions that had blurred or collapsed these two elements into a single inquiry, including Dillon, Golonka, and Gomulka, as well as language in Dart to the extent it blurred that distinction.  The Court further clarified the distinction between the two elements, explaining a product is defective when it is unsafe for normal handling or consumption.  Said another way, a defect is “a condition or characteristic of the product not reasonably contemplated by the ordinary consumer that renders the product unsafe for its intended use.”  By contrast, a product is unreasonably dangerous when it is “more dangerous than a consumer would expect or whose risks outweigh its benefits.”

The Court further clarified that the consumer expectation test and risk/benefit analysis are two tools for evaluating whether a defective product is unreasonably dangerous. They are not substitutes for the threshold defect inquiry.

Applying that framework, the Court concluded the 4Runner was not defective because ordinary drivers do not expect vehicles to prevent human error caused by careless driving and understand their fundamental responsibility to stay awake and remain in their lane. Thus, the absence of LDW technology does not render a vehicle unsafe for its ordinary, intended use. As a result, the Maywalds could not make the threshold showing of a defective product, meaning their strict liability, negligent design, and derivative loss of consortium claims all failed.

Although the absence of a defect was dispositive of the Maywalds’ claims, the Court went on to clarify the proper application of the risk/benefit analysis because of confusion in the lower courts. The Court agreed that the risk-benefit analysis, and not the consumer-expectation test, was the appropriate analysis to apply to the claim, but disagreed with how the court of appeals applied the risk/benefit analysis.

The Court held that when applying the risk/benefit analysis, the correct inquiry does not compare the challenged design to an alternative design that incorporates the technology. Instead, one must look at the risks or benefits inherent in the challenged design (here the vehicle without LDW technology). Said another way, the “inquiry … remains focused on whether the product, as designed and sold, was reasonably safe for its intended and ordinary use, not whether additional features could have made it safer.”  The Court emphasized that although evidence concerning the feasibility or utility of an alternative design may inform that analysis, it cannot supplant the inquiry into the risks and benefits of the challenged design itself.  The Court concluded that because the 4Runner’s lack of LDW technology did not render it defective, summary judgment in Toyota’s favor was proper.  It thus vacated the court of appeals’ decision, and affirmed the trial court’s grant of summary judgment to Toyota.