MAYWALD et al v TOYOTA et al, CV-25-0009-PR

Background

Shawn and Tanya Maywald were injured when a northbound 2019 Toyota 4Runner crossed the center line and struck their vehicle after its driver fell asleep. 1
The Maywalds sued Toyota for strict liability design defect, negligent design, and loss of consortium, alleging the 4Runner was defective and unreasonably dangerous because it lacked lane departure warning technology. 2
Toyota obtained summary judgment in the superior court, and the court of appeals vacated that ruling, reasoning the risk/benefit analysis could compare the 4Runner to a safer alternative design with LDW. 3
The supreme court granted review to decide whether Arizona strict product liability requires proof that a product is both defective and unreasonably dangerous and how to apply the consumer expectation and risk/benefit tests. 4
The court held a plaintiff must first prove defectiveness, then prove the defect rendered the product unreasonably dangerous, and it affirmed summary judgment for Toyota. 5
The court concluded the 2019 4Runner was not defective because the absence of LDW did not make it unsafe for ordinary use, and the risk/benefit analysis must focus on the challenged design itself, not an alternative design. 6

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Elements of strict product liability 7	Maywalds claimed defect and unreasonable danger merge into one showing.	Toyota argued Arizona requires separate proof of defect and unreasonable danger.	Arizona requires proof of both defect and unreasonable danger. 8
Whether the 4Runner was defective without LDW 9	Maywalds said omitting LDW made the 4Runner defectively designed.	Toyota argued the vehicle was safe for ordinary use and the absence of LDW was not a defect.	The 4Runner was not defective because lack of LDW did not make ordinary use unsafe. 10
Proper scope of risk/benefit analysis 11	Maywalds urged comparing the 4Runner to an LDW-equipped alternative.	Toyota said the analysis concerns the challenged design, not a safer alternative.	The analysis focuses on the challenged design’s risks and benefits, not alternative designs. 12
Negligent design claim 13	Maywalds contended Toyota negligently designed the 4Runner without LDW.	Toyota argued no negligence claim could proceed absent a defect.	The negligent design claim failed because the Maywalds could not show defect. 14
Loss of consortium claim 15	Maywalds sought consortium damages based on the underlying tort claims.	Toyota argued consortium is derivative and fails without a viable tort claim.	The consortium claim failed because the underlying claims failed. 16

Key Cases Cited

O. S. Stapley Co. v. Miller, 103 Ariz. 556 (Ariz. 1968) (adopted Restatement § 402A strict product liability 17)
Byrns v. Riddell, Inc., 113 Ariz. 264 (Ariz. 1976) (reaffirmed separate proof of defect and unreasonable danger 18)
Rogers v. Unimac Co., 115 Ariz. 304 (Ariz. 1977) (requires proof the defect made the product unreasonably dangerous and caused injury 19)
Dart v. Wiebe Mfg., Inc., 147 Ariz. 242 (Ariz. 1985) (recognized consumer expectation and risk/benefit tests for unreasonable danger 20)
Readenour v. Marion Power Shovel, 149 Ariz. 442 (Ariz. 1986) (distinguished defectiveness from unreasonable danger and defined both terms 21)
Gosewisch v. American Honda Motor Co., 153 Ariz. 400 (Ariz. 1987) (stated prima facie strict liability requires a defective condition and unreasonable danger 22)
Golonka v. General Motors Corp., 204 Ariz. 575 (Ariz. App. 2003) (treated consumer expectation or risk/benefit as establishing both elements, later disapproved 23)
Dillon v. Zeneca Corp., 202 Ariz. 167 (Ariz. App. 2002) (collapsed defectiveness and unreasonable danger into one showing, later disapproved 24)
Jimenez v. Sears, Roebuck & Co., 183 Ariz. 399 (Ariz. 1995) (recognized the modern prima facie strict liability framework 25)
Rosenberg v. Sanders, 256 Ariz. 359 (Ariz. 2023) (summary judgment standard reviewed de novo 26)
Barnes v. Outlaw, 192 Ariz. 283 (Ariz. 1998) (loss of consortium is derivative of an underlying tort claim 27)
Estabrook v. J. C. Penney Co., 105 Ariz. 302 (Ariz. 1970) (absence of evidence of defect defeats strict liability 28)
Brown v. Sears, Roebuck & Co., 136 Ariz. 556 (Ariz. App. 1983) (availability of an alternative safety feature alone does not make a product defective 29)
Berkoski v. Honda Motor Co., 328 A.3d 986 (N.J. Super. Ct. App. Div. 2025) (absence of an LDW system did not make a vehicle defectively designed 30)
Ortiz v. Daimler Truck North America LLC, 112 Cal. App. 5th 608 (Cal. Ct. App. 2025) (addressed duty and proximate cause, not whether the vehicle was defectively designed 31)
Mather v. Caterpillar Tractor Corp., 23 Ariz. App. 409 (Ariz. App. 1975) (negligent design asks whether reasonable care was used to make the product safe for intended uses 32)
Bailey v. Montgomery Ward & Co., 6 Ariz. App. 213 (Ariz. App. 1967) (defined a defective article as not reasonably fit for ordinary purposes 33)