20 Cal. 3d 413 (1978)
In August 1970, plaintiff Ray Barker was injured at a construction site at the University of California at Santa Cruz while operating a high-lift loader manufactured by defendant Lull Engineering Co. and leased to plaintiff's employer by defendant George M. Philpott Co., Inc.1
The loader was 23 feet long, 8 feet wide and weighed 17,050 pounds.2 It was designed to lift loads of up to 5,000 pounds to a maximum height of 32 feet.3
On the day of the accident the regular operator of the loader did not report for work.4 Plaintiff, who had received only limited instruction on the operation of the loader and had operated it on only a few occasions, was assigned to run the loader.5
The accident occurred while plaintiff was attempting to lift a load of lumber to a height of approximately 18 to 20 feet.6 The terrain on which the loader rested sloped sharply in several directions.7 When it appeared to several coworkers that the load was beginning to tip, the workers shouted to plaintiff to jump from the loader.8 Plaintiff leaped from the loader but while scrambling away he was struck by a piece of falling lumber and suffered serious injury.9
Plaintiff contended that the accident was attributable to one or more design defects of the loader.10 These included the absence of outriggers, the lack of a roll bar or seat belts, the design of the leveling mechanism, and the absence of a park position on the transmission.11 Defendants denied that the loader was defective in any respect.12 They claimed that the accident resulted either from plaintiff's lack of skill or from his misuse of the product.13
The jury returned a verdict in favor of defendants.14 The Court of Appeal affirmed the judgment.15 The Supreme Court granted plaintiff's petition for hearing to consider the propriety of the trial court's instructions on the law of products liability.16
The trial court instructed the jury on strict liability in tort.17 The trial court also instructed the jury that if the plaintiff voluntarily and unreasonably proceeded to encounter a known danger, then the plaintiff may not recover.18
Whether the trial court erred in instructing the jury that strict liability for a defect in design of a product is based on a finding that the product was unreasonably dangerous for its intended use?19
A manufacturer is strictly liable in tort when an article placed on the market proves to have a defect that causes injury to a human being.20 A plaintiff need only show that the product was defective and that the defect proximately caused the injuries.21 The Restatement's unreasonably dangerous formulation is rejected because it burdens the plaintiff with an element not essential to strict liability.22
Yes. The trial court instructed the jury that strict liability for a defect in design is based on a finding that the product was unreasonably dangerous for its intended use.23 Plaintiff Ray Barker was injured while operating the high-lift loader on a construction site.24 He contended that design defects including the absence of outriggers and a roll bar proximately caused his injuries.25
Under the rule the instruction improperly incorporated the rejected standard and limited evaluation to intended use rather than reasonably foreseeable use.26
The trial court erred in instructing the jury that strict liability for a defect in design of a product is based on a finding that the product was unreasonably dangerous for its intended use.27
Whether a trial court may properly instruct the jury on a dual standard for determining design defect that includes both the consumer expectations test and the risk-benefit test?28
A product is defective in design if the product has failed to perform as safely as an ordinary consumer would expect when used in an intended or reasonably foreseeable manner.29 A product is also defective in design if the benefits of the challenged design do not outweigh the risk of danger inherent in such design.30 In applying the risk-benefit test the jury may consider the gravity of the danger, the likelihood of its occurrence, the mechanical feasibility of a safer alternative design, the financial cost of an improved design, and the adverse consequences of an alternative design.31
Yes. The established facts demonstrate that the loader lacked outriggers, a roll bar, and seat belts.32 Plaintiff contended these absences constituted design defects causing his injuries when the load tipped on sloping terrain.33 Under the rule a trial court may properly instruct on both the consumer expectations test and the risk-benefit test.34 The consumer expectations test alone could not resolve whether the design was defective given the technical evidence on stability and alternative safety features.35
A trial court may properly instruct the jury on a dual standard for determining design defect that includes both the consumer expectations test and the risk-benefit test.36
Whether the trial court erred in instructing the jury that if the plaintiff voluntarily and unreasonably proceeded to encounter a known danger then he could not recover?37
The defense of assumption of risk is available in a strict liability action only when the plaintiff has unreasonably proceeded to use the product with knowledge of the specific defect and awareness that the defect would cause injury.38 An instruction that bars recovery upon a finding that the plaintiff voluntarily and unreasonably proceeded to encounter a known danger without limiting the defense to knowledge of the specific defect is erroneous.39
Yes. Plaintiff Barker had received only limited instruction and had operated the loader on only a few occasions.40 He leaped from the machine when the load appeared to tip and was struck by falling lumber.41 Under the rule an instruction on voluntary encounter of a known danger without the required limitations on knowledge of the specific defect is erroneous.42
The trial court erred in instructing the jury that if the plaintiff voluntarily and unreasonably proceeded to encounter a known danger then he could not recover.43
Whether the burden of proof on the risk-benefit factors in a design defect case should be allocated to the defendant once the plaintiff makes a prima facie showing that the design proximately caused the injury?44
Once the plaintiff makes a prima facie showing that the injury was proximately caused by the product's design, the burden shifts to the defendant to prove in light of the gravity of the danger, the likelihood of occurrence, the mechanical feasibility of a safer alternative design, the financial cost of an improved design, and the adverse consequences of an alternative design that on balance the benefits of the challenged design outweigh the risk of danger inherent in such design.45 This allocation relieves the plaintiff of onerous evidentiary burdens and places the burden on the party with knowledge of the technical design trade-offs.46
Yes. Plaintiff presented expert testimony that the loader was unstable due to its narrow base and should have had outriggers.47 The absence of a roll bar and seat belts was a proximate cause of injuries because plaintiff had no reasonable choice but to leap.48 Under the rule the burden on the risk-benefit factors properly shifts to defendants Lull Engineering and Philpott once this prima facie showing is made.49
The burden of proof on the risk-benefit factors in a design defect case should be allocated to the defendant once the plaintiff makes a prima facie showing that the design proximately caused the injury.50