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Defending Against "Malfunction Theory" in E-Cigarette Cases


In litigation involving injuries caused by electronic cigarettes, vaporizers, vape pens, and other electronic nicotine delivery system (ENDS) products (“e-cigs”), plaintiffs frequently claim that their injuries were caused by defective lithium-ion batteries overheating and combusting. However, the battery itself is sometimes incinerated in the accident, creating challenges for plaintiffs to prove that the battery was defective (and for defendants to mount a successful defense to such claims). This client alert addresses those issues, and provides recommendations for manufacturers, distributors, retailers, and others in the chain of distribution of e-cigs for developing a defense under such circumstances.

1. Background on Lithium-Ion Batteries in E-Cigs

E-cigs are typically handheld electronic devices that simulate tobacco smoking by vaporizing a liquid solution containing flavorings and (sometimes) nicotine. The vaporizing element is powered by a lithium-ion battery. Unfortunately, lithium-ion batteries can be subject to “thermal runaway,” where an internal chain reaction causes rapid overheating, ultimately resulting in destruction.

The problem of thermal runaway in lithium-ion batteries is not limited to e-cigs. The same concerns caused the grounding of the Boeing 787 Dreamliner fleet in 2013, the recall of half a million hoverboards in 2016, and the recall of Samsung’s Galaxy Note 7 smartphones that same year. However, some have suggested that e-cigs are more prone to catastrophic failure and physical injury due to their construction. Cellphones and other devices normally use “pouch” lithium-ion cells contained in plastic wrap. These cells can more readily accommodate small amounts of gas that naturally build up within the battery. E-cigarette batteries are typically encased in a metal can. The can-type batteries may be subject to greater internal pressure during thermal runaway, resulting in explosions. 

2. The “Malfunction Theory” of Product Liability

Although courts – and juries – prefer to have proof that a specific defect caused the alleged injury(ies), that is not always possible in cases where the product itself is destroyed, leaving little or nothing for expert analysis. Under the “malfunction theory” of product liability, the plaintiff may rely on circumstantial evidence of a malfunction from which a defect can be inferred. In other words, the malfunction itself may be circumstantial evidence of a defective condition. Many states have adopted the malfunction theory in one form or another. 

This theory derives from an almost 75-year-old case, Escola v. Coca Cola Bottling Co. of Fresno, 150 P.2d 436 (Cal. 1944), where a Coke bottle exploded in the hand of a waitress. The court held that the evidence supported an inference “that the bottle was in some manner defective . . . because sound and properly prepared bottles of carbonated liquids do not ordinarily explode when carefully handled.”  Id. at 459. 

Similarly, a Connecticut appellate court found sufficient circumstantial evidence for a jury to infer that a television set that ignited was defective. Liberty Mut. Ins. Co. v. Sears, Roebuck & Co., 406 A.2d 1254 (Conn. Super. Ct. 1979). During six months of normal use, the television set was never repaired, abused, or tampered with. This evidence, the court concluded, “together with the evidence that the set had in fact malfunctioned and the jury’s knowledge from common experience that television sets, in normal use, do not self-ignite, was sufficient to establish that the television set in question was defective.”  Id. at 1257.

3. Application of the “Malfunction Theory” in E-Cig Cases

The malfunction theory has not yet been argued in any reported e-cig cases, but a plaintiff has been successful with the theory in a lithium-ion battery case. See Sabo v. Fiskars Brands, Inc., No. 2:12-cv-503, 2014 WL 4365319 (D. Idaho Sept. 2, 2014). In Sabo, the plaintiff alleged that he had a lithium-powered flashlight in his pocket when it “spontaneously combusted,” causing injuries.  Multiple witnesses heard a popping sound similar to a gunshot and saw smoke coming from Mr. Sabo’s left front pants pocket.  Id. at *9. In opposing defendant’s motion for summary judgment, Mr. Sabo argued that the flashlight malfunctioned due to a defect that caused the battery to vent and the flashlight to explode. He argued that “[t]he explosion of the flashlight itself is the circumstantial evidence of malfunction.  Flashlights normally do not spontaneously combust while in the off position in one’s pocket.”  Id. at *14. Although the defendant argued that post-sale damage to the flashlight may have caused a screw to loosen and short the battery, the defendant adduced no evidence indicating that Mr. Sabo, or anyone else, used the flashlight improperly.  Id. at *16. Thus, the plaintiff met his “burden to show the flashlight malfunctioned and there [was] no other reasonable explanation for the malfunction other than a manufacturing defect.” Id. at *4.

As in Sabo, e-cig plaintiffs will likely argue that an explosion of the battery itself is evidence of a defect. As part of a thorough defense strategy, defendants should be proactive from the beginning of the case to explore evidence of alternative causes. Courts have held that alternative causes such as wear and tear, abuse, or damage to the product can defeat the manufacturing theory inference.

As one example, the e-cig may have been heavily used and subjected to rough handling, putting strain on the lithium-ion battery. In Roselli v. Gen. Elec. Corp., 599 A.2d 685 (Penn. Super. Ct. 1991), plaintiffs alleged that the glass carafe of a GE coffee maker shattered, spraying boiling coffee onto plaintiff and causing severe burns. However, the court affirmed summary judgment for GE, citing evidence that the coffee maker had been used for many years, and thus plaintiffs “failed to eliminate the realistic possibility the glass carafe broke because of its use and handling prior to the date of the incident.”  Id. at 689. The court found this to be an equally probable explanation for the breakage.

Another example of alternative causes is misuse. Reports indicate that a significant number of e-cig incidents are linked to improper batteries, incompatible chargers, over-charging, over-discharging, or physical modifications like stacking multiple batteries for more power or lowering the resistance of the heating coils to increase vapor.  See, e.g., U.S. Fire Admin., Electronic Cigarette Fires and Explosions in the United States 2009 – 2016 (July 2017) App. 2. In Metro. Prop. & Cas. Ins. Co. v. Deere & Co., 25 A.3d 571 (Conn. 2011), the plaintiff claimed that a lawn tractor manufactured by Deere caused a fire, damaging the insured’s home. Although the court found sufficient circumstantial evidence that the fire was caused by a fault in the tractor’s electrical system, the plaintiff had not sufficiently excluded other reasonably possible secondary causes of the defect.  Id. at 592. Specifically, the court pointed to evidence that the homeowners both reported that the tractor ran well for over four years, but started running roughly and backfiring repeatedly for several months since a tune-up and maintenance. Id. at 590.  “[N]o evidence was presented that the work performed on the tractor could not have damaged or caused problems with the tractor’s electrical system, resulting in the problems of which the homeowners complained and, ultimately the failure of the electrical system.” d. at 592.

These cases demonstrate the importance of alternative causes. Defendants in e-cig cases should explore alternative causes in such cases where plaintiffs rely on the malfunction theory. In particular, defendants should look for evidence of heavy use, rough handling, or misuse. This evidence may be used to defeat a plaintiff’s argument that the explosion of an e-cig battery itself is evidence of a defect.

For more information about how this may affect your business and/or current or pending litigation, please contact one of the attorneys on the E-Cigarette/Vape Team. 

The information presented is for educational and informational purposes and is not intended to constitute legal advice. Readers should consult their professional advisor. Any opinions expressed within this article are solely the opinion of the featured authors and not of Morris, Manning & Martin, LLP.