California High Court Adopts Sophisticated User Doctrine as Complete Defense in Product Liability Failure to Warn Cases

By Marina Slavin – In a change that will reshape the landscape of California product liability litigation, the California Supreme Court adopted the “sophisticated user” doctrine as a complete defense in actions premised on a defendant’s alleged failure to warn. Under the court’s decision in Johnson v. American Standard (April 3, 2008) ___Cal.4th ___ (S139184), manufacturers and distributors are relieved from their general duty to warn sophisticated or particularly knowledgeable users about a product’s inherent dangers when those dangers should reasonably be known to that class of users by reason of the class’s specialized education or experience.

In the case that prompted this landmark ruling, plaintiff William Johnson, a certified heating, ventilation, and air conditioning technician, alleged he suffered injury from the inhalation of phosgene gas created when he brazed refrigerant lines on an air conditioning unit. Johnson sued the manufacturer of the unit, American Standard, alleging it knew that phosgene gas would be created during brazing, but failed to provide an adequate warning regarding the risk.

Invoking the “sophisticated user” defense, American Standard moved for summary judgment. American Standard argued that it had no duty to warn because the risks associated with the creation of phosgene gas during brazing were widely known within the air conditioning maintenance and repair industry. The trial court granted summary judgment on this ground, which the Court of Appeal affirmed.

On review, the California Supreme Court officially adopted the sophisticated user doctrine as an affirmative defense in failure to warn cases, observing that the doctrine is a natural outgrowth of the widely recognized rule that there is no duty to warn of obvious dangers. Under the court’s holding, a manufacturer or distributor has no duty to warn members of a particular trade or profession about dangers that are obvious or generally known within that trade or profession.

Significantly, the court explained that a given plaintiff’s sophistication or knowledge regarding the risks associated with a particular product must be measured under an objective industry standard, not by the plaintiff’s actual knowledge or lack thereof. Applying this standard, the court charged Johnson with knowledge of the danger associated with phosgene gas exposure, citing Johnson’s training and professional standards in the air conditioning industry. Johnson’s deposition testimony showing that he did not actually know or appreciate the danger was held to be insufficient, as a matter of law, to defeat summary judgment.

In the wake of Johnson, the sophisticated user defense should be considered when a failure to warn claim is brought in California by a plaintiff that appears to be an experienced or knowledgeable user of the defendant’s product. Assertion of the doctrine should also be considered in the context of product liability class action litigation. A defendant’s demonstration that individual class members are not similarly situated because they belong to different industries or professions, and consequently would be expected to exhibit significant differences in knowledge, expertise, and sophistication with respect to the risks associated with a particular product, may provide a basis for defeating class certification.

We expect that Johnson and its progeny will have a significant impact on the ability of product manufacturers and distributors to successfully defend product liability lawsuits based on failure to warn.

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