United States: California Adopts Sophisticated User Doctrine In Products Liability Case

Last Updated: March 17 2009
Article by Gregory N. Harris

In April 2008, California joined the growing list of jurisdictions recognizing the sophisticated user exception to a manufacturer's duty to warn users of potential dangers of its products. The plaintiff in Johnson v. American Standard, Inc.1 was a trained heating, ventilation and air conditioning (HVAC) technician, claiming to have developed pulmonary fibrosis due to defendant's failure to warn him that welding refrigerant lines containing the refrigerant R-22 could create phosgene gas, inhalation of which can cause potentially fatal lung disease. In addition to his several years of work experience, plaintiff had completed a one year training program in HVAC and held several certifications, including an EPA "universal" certification.2 Evidence adduced during discovery demonstrated that, beginning in 1997, every time plaintiff bought R-22, he "received, and sometimes read, an MSDS" (material safety data sheet) that explained the risks associated with R-22.3 Lower courts dismissed the case on the grounds that plaintiff, as an HVAC technician, could reasonably be expected to know the hazards associated with welding refrigerant lines, obviating defendant's duty to warn of the hazards. The California Supreme Court upheld the ruling and confirmed the sophisticated user exception as a defense to products liability lawsuits in California.

California law holds manufacturers strictly liable for injuries caused by a failure to warn of dangers known to be inherent in using their products.4 Thus, manufacturers are obligated to provide warnings of known risks to afford product users the option of avoiding the product, or taking steps to minimize the risk of injury. Courts in some jurisdictions have declined to apply the sophisticated user exception in strict liability cases, holding it applicable only in negligence cases. The Johnson court however, emphasized that the exception is applicable to both strict liability and negligence cases because the crucial determination in both is causation.

Under the sophisticated user exception, a manufacturer has no duty to warn if it reasonably believes that the user will realize the dangerous aspect or nature of a product. Put another way, there is no duty to warn if a manufacturer has a reasonable basis to believe that lack of a warning will not be the cause of any injury to the expected user. The theory underlying the sophisticated user exception is that a failure to warn a party of a danger of which it was already independently aware cannot be the proximate cause of injury resulting from that danger since, already being aware of the danger, the party presumably would have chosen the same course of action if warned.

As the Johnson court explained, the exception is intended as an objective standard. Accordingly, the exception turns on what a user of certain training and experience "should have known," based on that training and experience, rather than a subjective assessment of what each user actually "did know" in spite of that training and experience. "In other words, even if a user was truly unaware of a product's hazards, that fact is irrelevant if the danger was objectively obvious."5 As the court observed, "individuals who represent that they are trained or are members of a sophisticated group of users are saying to the world that they possess the level of knowledge and skill associated with that class. If they do not actually possess that knowledge and skill, that fact should not give rise to liability on the part of the manufacturer."6 Because the sophisticated user exception is an affirmative defense, defendants will be required to offer proof that a user should have known of the dangers of a product by virtue of training, experience, or job/certification requirements, and when they should have known it.

An interesting element in the Johnson decision is the court's reference to an earlier set of consolidated federal court decisions applying California law to claims against manufacturers supplying asbestos-containing material to the U.S. Navy and attempting to use the sophisticated user exception to avoid liability.7 The court notes, with apparent approval, the federal court's observation that under California law, a manufacturer who supplied asbestos-containing material to the Navy, a "sophisticated user," is not completely absolved from liability, because the Navy's failure to warn employees of the dangers of asbestos was reasonably foreseeable. Although this distinction may initially seem contrary to the rule espoused in Johnson, the manufacturer is required to warn end users of product dangers. The sophisticated user defense is an exception to that rule, based on an assumption that certain end users, by virtue of learning and experience, are aware of related dangers. In the federal case cited, the Navy was "sophisticated," but it was not the end user. Rather, the end users were individuals employed by the Navy; it was these end users to whom the manufacturer owed a duty to warn. The manufacturer could not avoid liability by delegating its duty to warn to the Navy, without reasonable assurance that it would be done. Although the defendant manufacturer argued that the Navy was a sophisticated user, its argument made was more akin to a learned intermediary argument.8

Cases involving an intermediary distributor/supplier are often distinguishable from those involving a true learned intermediary, such as a doctor, because whereas a doctor's ethical and legal obligations to inform patients of risks and alternatives to medications support a reasonable expectation that he will provide such warnings, not all suppliers (e.g., the Navy) are under such an obligation. The touchstone of any defense claiming an exception to the duty to warn is whether, considering who will be using the product, it is reasonable not to include a warning. In this regard, the Johnson court observed that, "'[n]ot all warnings . . . promote user safety. Requiring manufacturers to warn their products' users in all instances would place an onerous burden on them and would 'invite mass consumer disregard and ultimate contempt for the warning process.'"9 The court's pronouncement of a public policy rationale for recognizing the sophisticated user exception in California is prescient and in line with the modern trend toward increased acceptance of the defense, which will likely gain ground in more jurisdictions in the future.10


1 74 Cal.Rptr.3d 108 (2008).

2 "'Universal' certification is the highest certification an HVAC technician can obtain from the EPA, and it allows those certified to work on, and purchase, refrigerant for large commercial air conditioning systems." Johnson, 74 Cal.Rptr.3d at 112 (citing 40 C.F.R. secs 821.154(m), 82.161 (2007)).

3 Id.

4 Although California courts recognize the distinction between negligence and strict liability causes of action, in the context of cases alleging a failure to warn, there is little practical difference.

5 Johnson, 74 Cal.Rptr.3d at 120. 6 Id. at 118.

7 In re Related Asbestos Cases, 543 F. Supp. 1142 (N.D. Cal. 1982).

8 The learned intermediary exception absolves a manufacturer of liability when an intermediary exists which is in a better position to warn the end user of product risks. The product supplier or manufacturer can therefore be discharged of its duty to warn the end user by instead warning the learned intermediary.

9 Johnson, 74 Cal.Rptr.3d at 119 (internal citations ommitted).

10 See, e.g., Jeffrey W. Kemp and Lindsy Nicole Alleman. The Bulk Supplier, Sophisticated User, and Learned Intermediary Doctrines Since the Adoption of the Restatement (Third) of Torts. 26 Rev. Litig. 927 (2007).

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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