Products Liability: The Consumer Expectation Test

When a product causes harm, how do courts decide if its design was dangerously defective? One of the most influential and intuitive answers in American tort law is the Consumer Expectation Test. This legal standard imposes liability on a manufacturer when a product fails to perform as safely as an ordinary consumer would expect when using it in a reasonably foreseeable manner. Understanding this test is crucial because it forms the bedrock of design defect claims in many jurisdictions, directly linking legal liability to the fundamental bargain between consumers and the marketplace. It forces us to examine not just engineering specifications, but the reasonable, everyday assumptions people make about the things they use.

Foundations of the Consumer Expectation Test

The Consumer Expectation Test finds its most famous articulation in the landmark case Greenman v. Yuba Power Products, Inc. (1963) and was later codified in the Restatement (Second) of Torts § 402A. The core philosophy is that manufacturers implicitly warrant that their products are safe for normal use. A product is defective in design if it is more dangerous than the ordinary consumer who purchases it, with the ordinary knowledge common to the community, would expect.

The test contains two critical, interdependent elements. First, the court must determine the perspective of the "ordinary consumer." This is not an expert or an engineer, but a hypothetical reasonable person with general community knowledge about the product. Second, it assesses the "reasonably foreseeable use" of the product. Liability is not limited to a product's intended use; it extends to any use, including misuse, that is reasonably foreseeable to the manufacturer. For example, using a chair as a step-ladder is often deemed foreseeable, and thus the chair must be safe for that use under the consumer expectation standard. The test’s power lies in its simplicity: it asks a jury a common-sense question about safety expectations, bypassing complex technical debates.

Application to Obvious Dangers Versus Latent Defects

The test applies very differently depending on whether a danger is open and obvious or hidden and latent. For obvious dangers—like the sharp blade of a kitchen knife or the heat from a coffee pot—the ordinary consumer generally expects the inherent risk. The law presumes that with obvious dangers, the consumer can adjust their behavior to avoid harm (e.g., by not touching the blade or the hot surface). Therefore, a product with an obvious danger typically does not fail the Consumer Expectation Test, as it performed as safely as expected.

In contrast, the test is most potent when applied to latent defects—dangers that are hidden or not apparent upon ordinary inspection. For instance, if a soda bottle explodes due to excessive carbonation pressure or an electric drill’s housing becomes lethally electrified due to faulty wiring, the ordinary consumer has no expectation of such catastrophic failure. The product has violated the fundamental safety assumption a consumer makes when purchasing a seemingly benign item. The latent nature of the defect means the consumer had no opportunity to guard against it, making the manufacturer’s liability under this test clear and compelling.

Limitations with Technologically Complex Products

A major criticism and limitation of the pure Consumer Expectation Test arises with complex products. How can an ordinary consumer form a reasonable safety expectation about the anti-lock braking system in a car, the firmware in a medical device, or the chemical composition of a pharmaceutical drug? Courts have recognized that jurors cannot simply rely on their intuition about what is "expected" for products whose inner workings are a mystery to the layperson.

In such cases, applying the test literally can lead to absurd results or let dangerously defective designs escape liability. For example, in Soule v. General Motors Corp., the California Supreme Court noted that the consumer expectation test is unsuitable for a complex collision scenario involving a car’s floorboard design, where the average consumer has no basis for expectations. The court reasoned that when a product’s performance is beyond the common experience, the jury lacks the benchmark to apply the test meaningfully. This limitation has driven many jurisdictions to modify or supplement the consumer expectation standard for intricate technological designs.

The Dual Test and Alternative Approaches

To address the limitations with complex products, many jurisdictions, including California after Barker v. Lull Engineering, have adopted a dual test approach for design defects. Under this rule, a plaintiff can prove a design defect in one of two ways: (1) by using the traditional Consumer Expectation Test, or (2) by proving the product’s design caused the injury and the defendant fails to prove that the benefits of the challenged design outweigh its inherent risks. This second prong is known as the risk-utility test.

The dual test approach provides flexibility. For simple products or latent defects, the intuitive consumer expectation analysis remains available. For complex products, the plaintiff can shift to the risk-utility framework, which involves a more technical, balancing analysis of factors like the gravity of the danger, the likelihood of injury, the feasibility of a safer alternative design, and the product’s utility. This hybrid system seeks to ensure that no dangerously defective product escapes liability simply because it is too complicated for a consumer to understand, while preserving the common-sense appeal of the consumer expectation standard where it fits.

Common Pitfalls

Assuming the Test Applies to All Defects: A common mistake is applying the consumer expectation test to all product issues. It is primarily a test for design defects. Manufacturing defects (a flaw in one unit) are typically evaluated under a simpler "deviation from intended design" standard, and failure-to-warn claims are analyzed separately based on the adequacy of instructions and warnings.

Confusing Consumer Expectation with Personal Expectation: Students and practitioners sometimes conflate the objective "ordinary consumer" standard with a particular plaintiff’s subjective expectations. The test is not what this consumer expected, but what the hypothetical, reasonable consumer in the community would expect. A plaintiff’s own lack of care or unusual assumption does not define the standard.

Overlooking the "Foreseeable Use" Requirement: Another pitfall is focusing solely on consumer expectations while neglecting the second element: reasonably foreseeable use. A product might be safe for its intended use but dangerously defective for a misuse that was plainly foreseeable (e.g., a lightweight plastic bottle not meant for carbonated beverages, but commonly used for them). Liability can attach if the misuse was foreseeable.

Misapplying the Test to Obvious Dangers: Attempting to use the consumer expectation test to challenge a product with an open and obvious danger is usually futile. The proper claim in such scenarios is often a failure-to-warn (if a warning was needed about the severity of the risk) or a claim under the risk-utility test, not a consumer expectation design defect claim.

Summary

• The Consumer Expectation Test holds a product design defective if it fails to perform as safely as an ordinary consumer would expect during reasonably foreseeable use, providing an intuitive, common-sense standard for liability.
• The test is most effective for latent defects (hidden dangers) but generally does not apply to obvious dangers, as consumers are presumed to expect and avoid inherent, apparent risks.
• A key limitation is its problematic application to technologically complex products, where ordinary consumers lack the experience to form meaningful safety expectations about the engineering design.
• To address this, many jurisdictions use a dual test, allowing plaintiffs to proceed under either the consumer expectation standard or a risk-utility balancing test, ensuring dangerous designs of complex products are not shielded from liability.
• Successful application requires carefully distinguishing between the objective "ordinary consumer" perspective and a plaintiff’s subjective view, and always pairing safety expectations with an analysis of reasonably foreseeable use, not just intended use.