In The Paradox of Continuing Risk, W. Jonathan Cardi, Ashton Jenne, and Chance Villarreal surface and incisively explore a consequential puzzle. Across the United States, 32 jurisdictions have adopted the continuing-risk rule, which imposes an affirmative duty to warn, protect, or rescue others from continuing risks created by one’s conduct. But despite the multitude of courts that have endorsed the rule—and the rule’s unbroken acceptance in various Torts Restatements—few actual cases apply this principle.
To start, it’s important to understand what exactly the continuing-risk rule does and why it matters.
The rule is well-summarized in the Restatement Third of Torts: Liability for Physical and Emotional Harm § 39. Published in 2012, § 39 provides: “When an actor’s prior conduct, even though not tortious, creates a continuing risk of physical harm of a type characteristic of the conduct, the actor has a duty to exercise reasonable care to prevent or minimize the harm.”1
The idea, then, is that a doctor who implanted a Dalkon Shield in a patient before the IUD’s dangers came to light has an affirmative duty to warn the patient once those risks become apparent.2 If it weren’t for the rule, a doctor who breached no duty to the patient at the time of the IUD’s implantation—and took no action thereafter—would presumably face no liability.
Or think of a driver whose car suddenly stalls, creating a dangerous condition for fellow motorists. Under the continuing-risk rule, the driver has a duty reasonably to mitigate the hazard.
Or suppose a manufacturer sells a product that initially seems safe, but the risk of the product gradually becomes apparent. Under the ALI’s Product Liability Restatement, assuming the risk is significant, the seller has a limited duty to warn.3
Or finally, consider this scenario, adapted from an Illustration in the First Restatement:
Reasonably believing his car is in good repair, one Friday afternoon, Mel lends his vehicle to his next-door neighbor, Fielding. Later that evening, Mel’s wife mentions to him that, when she was driving the car earlier in the day, the vehicle’s brakes were sluggish and unresponsive. Mel doesn’t pass this information along. Unaware that the brakes are on the fritz, on Saturday morning, Fielding drives the car as he had planned. The brakes fail, and Fielding is injured in the ensuing collision.
The First Restatement explains that, pursuant to the continuing-risk rule, Mel is subject to liability to Fielding, even though, at the moment he acted (on Friday afternoon, when he handed off his keys to Mel), he was personally free of blame.4
Essentially then, the continuing-risk rule reverses the classic no-duty-to-rescue rule. But critically, it does so only in a discrete and narrowly defined set of circumstances. One narrowing mechanism involves characteristic risk. The rule does not impose liability whenever the defendant sets in motion a chain of events that eventually culminates in any conceivable injury to the plaintiff. Instead, per the Third Restatement, the continuing-risk rule applies only when the harm that befalls the plaintiff is “of a type characteristic of the [defendant’s] conduct.” Elaborating on this restriction, an Illustration provides:
Bill, who has two tickets to a basketball game between Wake Forest University and the University of Texas, takes his friend Mike, a Wake Forest fan, along. At the end of the game, Mike, distracted by the trouncing his team suffered, slips and falls down several rows of stairs and seriously injures himself. Bill, who is nearby at the time of the fall, has no duty of care to Mike to assist him pursuant to this Section, even though Bill, by taking Mike to the game, is a factual cause of Mike’s harm. Merely taking a friend to a sports event does not create a characteristic risk of slipping and falling.5
Another limitation is also critical (and easily overlooked): Like other affirmative-duty rules, the continuing-risk rule—even when it applies—merely opens the door to liability. It doesn’t establish it. In the stalled motorist scenario set forth above, for instance, the driver might take no precaution and still (appropriately!) face no liability. Perhaps given the road conditions, it is entirely reasonable for a stranded motorist to simply sit tight.
But, even with both these key caveats, it’s clear that the continuing-risk rule is a useful resource for many plaintiffs. Without it, given the defendant’s (at least recent) nonfeasance, it’ll be hard to establish a duty. With it, the duty element (at least) is satisfied.
It is surprising, then, as Professor Cardi and co-authors show: Although the continuing-risk rule is on the books in a strong majority of states, its actual application is exceptional. According to the authors, only in Texas and West Virginia is the rule cited frequently. In all other jurisdictions, fewer than ten cases have relied on it.
Adding to the mystery: This limited reliance can’t be chalked up to a lack of cases with congenial fact patterns. To the contrary, Cardi and co-authors identify numerous cases involving facts where the application of the continuing-risk rule would have given rise to a clear-cut defendant-side duty. Yet, in many of these cases, even while the duty question was exhaustively debated, the rule was never so much as mentioned.
So, Cardi and co-authors ask: Why has the continuing-risk rule continually fallen under the radar?
One potential culprit is simple ignorance. Judges and lawyers might not be aware of the rule—and this lack of awareness can create a negative feedback loop. “Courts fail to apply the rule, so attorneys fail to argue it, which in turn makes courts even less likely to apply it.” (P. 19.)
Or, it could be that judges and lawyers believe that the rule is too amorphous or open-ended, not realizing that, in fact, the Third Restatement’s version of the Rule (as explained above) contains clear and workable limits.6
But, for current purposes, the why is much less important than the simple fact. The continuing-risk rule is a broadly accepted doctrine that elegantly addresses factual scenarios that at least sometimes arise. By shining a light on this long-overlooked doctrine, Cardi, Jenne, and Villarreal perform a valuable service, assisting both litigants and courts.
- The rule’s articulation in the First Restatement of Torts is similar. Published in 1934, that Restatement’s § 321 provided: “If the actor does an act, which at the time he has no reason to believe will involve an unreasonable risk of causing bodily harm to another, but which, because of a change of circumstances or fuller knowledge acquired by the actor, he subsequently realizes or should realize as involving such a risk, the actor is under a duty to use reasonable care to prevent the risk from taking effect.” Restatement of Torts § 321 (Am. L. Inst. 1934). A generation later, the Second Restatement simplified things—but kept the basic gist: “If the actor knows or has reason to know that by his conduct, whether tortious or innocent, he has caused such bodily harm to another as to make him helpless and in danger of further harm, the actor is under a duty to exercise reasonable care to prevent such further harm.” Restatement Second of Torts § 322 (Am. L. Inst. 1965).
- See Tresemer v. Barke, 150 Cal. Rptr. 384 (Ct. App. 1978).
- See Restatement Third, Torts: Product Liability § 10 (Am. L. Inst. 1998); see also Walton v. Avco Corp., 610 A.2d 454, 459 (Pa. 1992).
- This Illustration is adapted from Illustration 2, set forth in the First Restatement of Torts § 321 (Am. L. Inst. 1934).
- Restatement Third, Torts: Liability for Physical and Emotional Harm § 39, Illustration 4 (Am. L. Inst. 2012).
- See id. (discussing the qualification based on characteristic risk).






