Morrison Law Journal
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The Morrison Law Journal
December 2013
Volume VIII, Edition 12

How Sophisticated Does A User Have To Be? Court of Appeal Rules
That, In Order To Establish Sophisticated User Defense, Manufacturer
Must Demonstrate that Sophisticated User Of Product Knew What Risks
Were And How To Use Product To Reduce Or Avoid Risks Of Use

By: Edward F. Morriso n, Jr., Esq.
Larry A. Schwartz, Esq.

In a decision which will likely clarify the "Sophisticated User" defense in products liability cases, the California Court of Appeal, Fifth District, ruled in Buckner v. Milwaukee Electric Tool Corporation (2013) WL6709458 ("Buckner") that, in order to establish the sophisticated user defense, a manufacturer must demonstrate that the user of the product knew what the risks of use were, including the degree of danger involved (i.e., the severity of the potential injury), and how to use the product to reduce or avoid the risks to the extent that information is known to the manufacturer. The Buckner decision provides some clarification with respect to the California Supreme Court's decision in Johnson v. American Standard, Inc. (2008) 43 Cal.4th 556 ("Johnson").

As many are aware, in 2008, by way of its holding in the Johnson case, the California Supreme Court recognized the sophisticated user defense to a cause of action for failure to warn in a products liability case. In Johnson, the plaintiff, a trained and certified heating, ventilation and air conditioning technician, alleged the defendant, manufacturer of air conditioning equipment, was negligent and strictly liable for injuries he sustained because the defendant manufacturer failed to warn the plaintiff that brazing the refrigerant lines to repair the air conditioning equipment would create phosgene gas, the utilization of which could result in potentially fatal lung disease. Following the grant of Summary Judgment in favor of the defendant manufacturer, the California Supreme Court held that, under the sophisticated user defense, sophisticated users need not be warned of the dangers they are already aware or should be aware because the sophisticated user is charged with knowing the dangers in using the particular product and the failure to warn about those dangers is not the legal cause of any harm that the product may cause.

California cases, however, have not specifically defined the danger that needs to be generally known in the trade, professional or other group for members of that group to be considered sophisticated users who require no


warning of the danger. That question has been answered, at least in part, in the Buckner case.

In Buckner, the plaintiff was employed by the Central California Tristeza Eradication Agency to do maintenance work. On October 7, 2009, he was using a power drill to drill a hole in a piece of angle iron when the drill bit bound and counter rotated, twisting his arm and causing serious injuries. The drill was manufactured by Milwaukee Electric Tool Corporation some 17 years earlier. The plaintiff's theory at trial was that the drill could not be used safely without a side handle, also known as an anti-torque bar. The plaintiff also contended that the drill was negligently and defectively designed because it did not include an interlock device that would prevent the drill from being used when the side handle was not attached. The drill originally did come with a side handle, which could be installed on either side of the drill for left or right handed use, however the operating manual and the side handle were not provided to the plaintiff.

In its verdict, the Trial Court jury found the drill was not negligently or defectively designed. However, the jury did not determine whether there was a failure to warn or inadequate warning, because it resolved the failure to warn issue by finding the plaintiff was a sophisticated user. The Trial Court, finding that there was insufficient evidence that the dangers complained of by plaintiff were common knowledge to maintenance workers, ordered a new trial on the sophisticated user defense.

Milwaukee Electric Tool Corporation appealed the Trial Court's order for a new trial and the Trial Court's pre-trial denial of that defendant's Motion for Summary Judgment which was based upon the sophisticated user defense. The Court of Appeal affirmed the rulings of the Trial Court. In that regard, the Court of Appeal held that, in order to establish the sophisticated user defense, the defendant must identify the relevant risk, show that any sophisticated users are already aware of the risk, and demonstrate the plaintiff to be a member of the group of sophisticated users. In that regard, the Court of Appeal ruled the scope of knowledge of the sophisticated user must parallel the scope of the warning that would otherwise have been required and that did not occur in this case.

The Buckner decision will certainly have an impact on the sophisticated user defense and in particular for users such as maintenance personnel.

About the Authors: Edward F. Morrison, Jr. is the founding partner and Larry A. Schwartz is Of Counsel to The Morrison Law Group, a professional corporation. Their biographies can be viewed at


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