The cause of the plaintiff’s damages is typically the first and most critical question posed to a jury in a product liability trial. If a jury determines that a substantial factor in the cause of the plaintiff’s damages was a natural event, such as lightning, a tornado or some other weather-related event, the defendant is not held liable. The act of God defense has been around since the 1800s and, if successfully proven at trial, can serve as a complete defense to a product liability claim. For a variety of reasons, however, the act of God defense has been streamlined by most courts and its viability is being tested in product liability litigation around the nation.

The case that first recognized this defense was Gleeson v. Va. Mid. Ry., 140 U.S. 435, 11 S. Ct. 859 (1891). In Gleeson, the United States Supreme Court held that parties could not be liable for injuries and sudden deaths caused by extraordinary floods, storms of unusual violence, sudden tempests, severe frosts, great droughts, lightning and earthquakes.

The United States Congress defined an act of God as “an unanticipated, grave natural disaster or other natural phenomenon of an exceptional, inevitable and irresistible character, the effects of which could not have been prevented or avoided by the exercise of due care or foresight.” See the Oil Pollution Act, 33 U.S.C. § 2701(1) (2006); and in the Comprehensive Environmental Response, Compensation, and Liability Act, 42 U.S.C. § 9601(1) (2006).

Nonetheless, the mere fact that a natural event, such as lightning, strong winds or a flood, may have occurred and brought about the plaintiff’s injuries or damages does not insulate the defendant from potential liability. The following are important factors that the defendant should be prepared to prove when asserting an act of God defense: (1) was there a duty owed to the plaintiff by the defendant, (2) were the event and attendant harm foreseeable, (3) how often, if ever, has this type of natural event occurred previously, and (4) was the defendant negligent? If it is found that the defendant was negligent and the defendant’s negligence was a proximate cause of the plaintiff’s harm, an act of God defense will not be successful.

The act of God defense is not always a “slam dunk” for the defendant and requires more than a showing by the defendant that the natural phenomenon occurred. The defendant must still prove that the act of God was the proximate cause for the plaintiff’s injury, i.e., the defendant’s negligence was not a factor in the cause of the plaintiff’s injury. Thus, in most cases, a defendant cannot expect to use this defense to support a motion for summary judgment. The issue will have to be decided by a jury, or in the case of a bench trial, by a judge. Moreover, “foreseeability” is a critical factor in the negligence calculation. As storms and significant weather events increase in frequency over time possibly due to climate change, plaintiffs have argued that these extreme natural events have become more commonplace and predictable. Plaintiffs’ attorneys also rely on the fact that recent innovations in communication and weather forecasting technology have made it more difficult for defendants to argue that some natural events are not foreseeable. However, the act of God defense still plays an important role in product liability litigation and should not be overlooked by a defendant who may be facing claims of product defect where it is clear that the plaintiff’s injuries were beyond the defendant’s control due to an extreme natural phenomenon.