California Civil Jury Instructions (CACI) - 1204. Strict Liability—
Design Defect—Risk-Benefit Test—Essential Factual Elements—Shifting Burden of Proof

[Name of plaintiff] claims that the [product]’s design caused harm to [name of plaintiff]. To establish this claim, [name of plaintiff] must prove all of the following:

1. That [name of defendant] [manufactured/distributed/sold] the [product];
2. [That, at the time of the use, the [product] was substantially the same as when it left [name of defendant]’s possession;]
   [or]
   [That any changes made to the [product] after it left [name of defendant]’s possession were reasonably foreseeable to [name of defendant];]
3. That the [product] was used [or misused] in a way that was reasonably foreseeable to [name of defendant]; and
4. That the [product]’s design was a substantial factor in causing harm to [name of plaintiff].

If [name of plaintiff] has proved these four facts, then your decision on this claim must be for [name of plaintiff] unless [name of defendant] proves that the benefits of the design outweigh the risks of the design. In deciding whether the benefits outweigh the risks, you should consider the following:

1. The gravity of the potential harm resulting from the use of the [product];
2. The likelihood that such harm would occur;
3. The feasibility of an alternative design;
4. The cost of an alternative design; [and]
5. The disadvantages of an alternative design; [and]
6. [Other relevant factor(s)].

If both tests for design defect (the consumer expectation test and the risk-benefit test) are asserted by the plaintiff, the instructions must make it clear that the two tests are alternatives. (Bracisco v. Beech Aircraft Corp. (1984) 159 Cal.App.3d 1101, 1106-1107.)

Some cases state that product misuse must be pleaded as an affirmative defense. (See, e.g., Williams v. Beechnut Nutrition Corp. (1986) 185 Cal.App.3d 135, 141.) However, the advisory committee that absence of unforeseeable misuse is an element of plaintiff’s claim and that foreseeable misuse is more properly asserted by defendant in support of a claim of contributory negligence. But see below:

Sources and Authority:

• Under the risk-benefit test, the plaintiff does not have to prove the presence of a defect. Rather, once the plaintiff makes a prima facie showing that the product’s design caused the injury, the burden shifts to the defendant to prove the design was not defective. A jury instruction stating that the plaintiff had the burden of proving that a design was defective in a case based on the risk-benefit test was held to be error in Moreno v. Fey Manufacturing Corp. (1983) 149 Cal.App.3d 23, 27, and in Lunghi v. Clark Equipment Co., Inc. (1984) 153 Cal.App.3d 485, 498.
• The jury should be directed to consider several factors in deciding whether the risks of a design outweigh its benefits. Among the relevant factors are: “the gravity of the danger posed by the challenged design, the likelihood that such danger would occur, the mechanical feasibility of a safer alternative design, the financial cost of an improved design, and the adverse consequences to the product and to the consumer that would result from an alternative design.” (Bernal v. Richard Wolf Medical Instruments Corp. (1990) 221 Cal.App.3d 1326, 1331–1332, internal citation omitted, disapproved and overruled on another point in Soule v. General Motors Corp. (1994) 8 Cal.4th 548, 580.)
• The plaintiff does not have to prove the existence of a feasible alternative design. (Bernal, supra, 221 Cal.App.3d at p. 1335.)
• This instruction should not be used in connection with the consumer expectation test for design defect: “Risk-benefit weighing is not a formal part of, nor may it serve as a ‘defense’ to, the consumer expectations test.” (Bresnahan v. Chrysler Corp. (1995) 32 Cal.App.4th 1559, 1569, internal citation omitted.)

Secondary Sources:

• 6 Witkin, Summary of California Law (9th ed. 1988) Torts, §§ 1254–1264
• California Products Liability Actions, Ch. 7, Proof, § 7.02 (Matthew Bender)
• California Forms of Pleading and Practice, Ch. 460, Products Liability, § 460.11 (Matthew Bender)
• California Points and Authorities, Ch. 190, Products Liability (Matthew Bender)