The Arizona Supreme Court's July 7 decision in Maywald v. Toyota Motor Corp., No. CV-25-0009-PR, is the rare products opinion that rewires the elements of the claim itself. For plaintiff lawyers filing strict-liability cases in Arizona, it changes both what you have to prove and how you prove it. For anyone building a safety-feature-omission theory anywhere, it is a warning about how courts are treating driver-assistance technology.
The facts
In 2019, Shawn and Tanya Maywald were struck head-on by a Toyota 4Runner whose driver had fallen asleep at the wheel. The Maywalds sued Toyota on a strict-liability design-defect theory, arguing that the 4Runner was defective because it lacked lane-departure warning technology that, they contended, could have alerted the drowsy driver and prevented the crash. The theory was a familiar one: not that a component failed, but that the vehicle was unsafe because a feasible safety feature had been left out.
The holding
The court held that an Arizona plaintiff pursuing strict product liability must independently establish two elements: that the product was defective, and that the defect rendered the product unreasonably dangerous. It disapproved prior appellate decisions that had collapsed those two questions into one. The court defined a defect as a condition or characteristic of the product not reasonably contemplated by the ordinary consumer that renders the product unsafe for its intended use, and it defined unreasonably dangerous in terms of danger beyond what a consumer would expect, or risks that outweigh the benefits.
Applying that framework, the court concluded the 4Runner was not defective. Ordinary drivers, it reasoned, understand their own responsibility to stay awake and attentive, and they do not expect a vehicle to prevent the consequences of their own careless driving. Because a reasonable consumer would not expect the vehicle to compensate for the driver's failure to stay awake, the absence of lane-departure warning did not render the 4Runner unsafe for ordinary use, and the strict-liability claim failed.
One more piece of the opinion deserves attention. On the risk-benefit side of the analysis, the court said the inquiry should focus on the risks inherent in the challenged design itself, not on a comparison with an alternative design. That is a meaningful divergence from the reasonable-alternative-design model that dominates modern products practice and that most retained design experts are trained to apply.
Plaintiff and defense theories
The plaintiff theory was a crashworthiness-adjacent argument dressed as a design defect: the vehicle should have included available technology that would have mitigated a foreseeable form of driver error. The defense answered with consumer expectations, and the court agreed that an ordinary consumer does not expect a car to police the driver's alertness. The gap between those two positions is the whole case, and it is where future Arizona plaintiffs will have to win or lose.
What it means for case-building
Three practical consequences follow for Arizona filings.
- Plead and prove both elements separately. Do not assume a showing of defect carries unreasonable danger with it. Structure the complaint, the expert disclosures, and the verdict form around two distinct findings, because the court has now said they are distinct.
- Safety-feature-omission theories just got harder. If your defect theory is that the manufacturer should have included a driver-assistance feature, Maywald supplies the defense a ready answer grounded in consumer expectations. The stronger versions of these cases will tie the missing feature to a hazard the driver could not reasonably manage alone, not to ordinary inattention.
- Mind the risk-benefit framing. Because the court centered the inherent risks of the design rather than a safer-alternative comparison, plaintiff experts should be prepared to speak to the danger of the design as sold, not only to the existence of a better option. Leading only with a reasonable-alternative-design opinion may not fit the test the court articulated.
The larger pattern
Maywald lands in the middle of a broader argument about who bears the risk of automated and semi-automated driving features. Plaintiffs have pressed the position that once a technology is feasible and marketed as a safety benefit, its absence can be a defect. Courts, including Arizona's now, are pushing back where the omitted feature would have functioned mainly to correct the driver's own conduct. The line the opinions are drawing separates features that address hazards outside the driver's control from features that substitute for basic driver responsibility. Plaintiff lawyers should build their driver-assistance-omission cases on the correct side of that line, and should expect defense counsel to cite Maywald for the proposition that a consumer never expects the car to backstop the driver's own inattention.
The decision is binding only in Arizona, but its reasoning will travel, particularly the consumer-expectations analysis of optional safety technology. Practitioners in other states should read it as a preview of the defense argument they will face. For related coverage, see our case law and settlements archive, our practice pieces in product liability, and the driver-assistance evidence issues discussed across our auto accidents coverage.