Issues & Arguments Negligence

The special problem of intervening cause

Written by: Thomas A. Downie September 28, 2022 Read Time: 5 min

This post is part of a series. Here is the full series list:

  1. Pleading the element of duty
  2. The duty element revisited
  3. The special problem of intervening cause

This is the last post in a three-part series on the “duty” element in a negligence case. As I’ve mentioned, the duty element and proximate cause are interrelated, in that they both depend on “foreseeability.”  This third post spills over into proximate cause to some extent. That element warrants further attention in future posts. 

The matter of “intervening cause” intrigued me when it arose in torts class. We’d learned Palsgrafs “foreseeability” test, which came into play on both the “existence of a duty” and proximate cause. See Pleading the element of duty. Then foreseeability appeared again in conjunction with “intervening cause.” But there it functioned as a kind of double-negative—providing a defense in some situations, but then potentially negating that defense.

The rules of intervening cause are summarized below. I’ve also mentioned some factual situations in which intervening cause can be especially problematic.

Rules on Intervening Cause

The problem arises when a third party enters the picture and contributes to the plaintiff’s injury. Does the “intervening cause” exculpate the original tortfeasor? 

Courts generally hold that “[a] person who has been negligent … is not liable for the [plaintiff’s] damages … when some separate force or action is ‘the active and efficient intervening cause.’” Gibson v. Avis Rent-A-Car System, Inc., 386 So.2d 520, 522 (Fla. 1980). However, the original tortfeasor’s action need not be “the sole cause” in order to be actionable, nor “the last act, or the one nearest to the injury, provided it is a substantial factor in producing the end result.” McClenahan v. Cooley, 806 S.W.2d 767, 775 (Tenn. 1991). Thus “one who is negligent is not absolved of liability when his conduct ‘sets in motion’ a chain of events resulting in injury to the plaintiff.” Gibson, 386 So.2d at 522. 

Enter the “foreseeability” test of Palsgraf. The third party’s act “is not a superseding, intervening cause so as to relieve the original wrongdoer of liability,” provided it “could have reasonably been foreseen” by the original tortfeasor. McClenahan, 806 S.W.2d at 775. This assumes that the tortfeasor’s conduct was still “a substantial factor in bringing about the harm.” Id.

Stating the rule conversely, “[t]he policy of the law on questions of intervening and superseding cause has evolved to the rule that the original actor is relieved from liability for the final result when, and only when, an intervening act of another was unforeseeable by a reasonable person in the position of the original actor and when, looking backward, after the event, the intervening act appears extraordinary.” Ontiveros v. Borak, 136 Ariz. 500, 667 P. 2d 200 (1983).

Thus, “foreseeable intervening forces” are “within the scope of the original risk” created by the tortfeasor’s negligence. Courts “are quite generally agreed that intervening causes which fall fairly in this category will not supersede the defendant’s responsibility.” Moning v. Alfono, 400 Mich. 425, 441, 254 NW 2d 759 (1977).

Emotionally Charged Cases

Intervening cause analysis works well even in technically-complex cases, such as ones involving engineering issues or product design. Still, difficult cases do arise.

In McClenahan, the defendant left his car in a public parking lot with the keys in the ignition. The car was stolen and “a high-speed chase” ensued. The thief “slammed into another vehicle broadside,” killing a pregnant woman and her four-year-old child. See McClenahan v. Cooley, 806 S.W.2d 767, 769 (Tenn. 1991). The trial judge granted judgment on the pleadings, holding that that “the intervening negligence of the thief insulated the Defendant from liability.” Id. at 770. 

The Tennessee Supreme Court reversed. The court rejected the contention “that an intervening criminal act under the circumstances presented here automatically breaks the chain of causation as a matter of law.” Id. at 776. Rather, the defendant “[c]ould have foreseen the theft of an unattended automobile with the keys in the ignition left in an area where the public has access, and could likewise foresee the increased risk to the public should a theft occur.” Id.

A Texas case was also heart-wrenching.  A “brutal assault and murder” of two teenage girls was committed “by six teenage gang members who had been drinking beer before the attack.” Phan Son Van v. Pena, 990 S.W.2d 751, 752 (Tex. 1999). The victims’ families sued the food store that “negligently sold alcohol to the underage gang members.” Id. The Texas Supreme Court affirmed the entry of summary judgment, holding that “the gang members’ intentional, violent criminal acts were not foreseeable and were a superseding cause of the girls’ deaths.” Id. at 756. While “[i]t is foreseeable … that the sale of alcohol to a minor will result in the minor driving while intoxicated,” the conduct of the gang members “was different in kind.” Id. at 756. “[T]he intentional sexual assault and brutal murder of two teenage girls who happen upon a gang initiation” would not “ordinarily result from such a sale.” Id.

Both of these decisions could be questioned. A “high-speed chase” resulting in several deaths seems to be a remote consequence of leaving car keys in the ignition. In the Texas case, on the other hand, furnishing alcohol to a teen who is not only a minor but also a known gang member does seem to give rise to a foreseeable risk of mayhem.

For current purposes, the point is simply that emotionally-charged situations might transcend the usual rules applicable to “[f]oreseeable intervening forces.” Moning, 400 Mich. at 441.

About The Author

I’ve litigated class actions and other complex cases for many years, roughly divided between plaintiffs’ practice and defense representation. My undergraduate degree is from Penn State University and I earned my law degree, cum laude, from Cleveland-Marshall College of Law. In my senior year I was elected Editor-in-Chief of the Cleveland State Law Review.