⚡ 10-Second Rule
Some activities are so risky that whoever runs them pays for the harm, even if they were super careful.
🧒 ELI-10 Scene
Dev deep-fries a turkey in his driveway every Thanksgiving. He reads the manual. He wears gloves. He keeps a fire extinguisher two feet away. But hot oil is hot oil. One splash burns a hole in his neighbor Priya's car cover. Priya doesn't have to prove Dev was sloppy. Dev chose to run a mini volcano next to her driveway. He got the fun, so he carries the risk. Careful or not, the bill lands on Dev.
⚖️ Actual Rule
Under the Restatement (Second) of Torts §§ 519–520, a person who carries on an abnormally dangerous activity is liable for the harm it causes, even without any negligence, but only for the kind of harm whose risk makes the activity abnormally dangerous in the first place. Section 520 lists six weighing factors: how likely the activity is to cause harm; how serious that harm would be; whether reasonable care can eliminate the risk; whether the activity is a matter of common usage; whether the location is appropriate for it; and whether the activity's value to the community outweighs its dangers. The Restatement (Third) of Torts: Liability for Physical and Emotional Harm § 20 condenses this: the activity must create a foreseeable and highly significant risk of physical harm even when reasonable care is exercised, and it must not be one of common usage. Under Restatement (Second) § 524A, there is no strict liability where the harm occurs only because the plaintiff's activity is abnormally sensitive. In modern comparative-fault jurisdictions, the plaintiff's own negligence reduces recovery rather than barring it (Restatement (Third) of Torts: Liability for Physical and Emotional Harm § 25). [NJ-VARIANT: flagged for future Eli Explains NJ Law module]
The doctrine traces to the Rylands v. Fletcher litigation, where Blackburn, J. wrote in the Exchequer Chamber, Fletcher v. Rylands, L.R. 1 Ex. 265, 279 (1866) — later approved by the House of Lords, Rylands v. Fletcher, L.R. 3 H.L. 330 (1868) — that "the person who for his own purposes brings on his lands and collects and keeps there anything likely to do mischief if it escapes, must keep it in at his peril."
ELI-10 translation: run a truly risky show, and you pay for the scary kind of harm it causes — no fault needed.
🔍 Ask These Questions
- Is the activity abnormally dangerous under the § 520 factors — blasting, storing explosives, fumigating with toxic gas, crop dusting? (Is this thing scary-risky even when everyone does it right?)
- Would reasonable care fail to eliminate the risk, and is the activity not common usage? (Even careful people can't tame it, and normal folks don't do it daily.)
- Is the defendant the one carrying on the activity? (Only the person running the risky show pays automatically.)
- Did the harm flow from the very risk that makes the activity dangerous — the scope-of-risk limit? (The scary part itself must cause the hurt, not some sideways accident.)
- Was the plaintiff's use abnormally sensitive? (If only an unusually fragile setup got hurt, strict liability drops out.)
- Did the plaintiff's own carelessness contribute? Under comparative fault, recovery shrinks but usually survives. (If the victim was careless too, the payout gets smaller, not erased.)
⚠️ Bar Trap
Exam language: Examiners stuff the fact pattern with the defendant's meticulous precautions — licensed engineers, state-of-the-art equipment, full regulatory compliance — and bait you into answering that due care defeats liability. The mirror-image trap runs the other way: strict liability is not absolute liability, so harm outside the activity's characteristic risk, or harm to an abnormally sensitive use, escapes the doctrine.
ELI-10: Being careful is no defense here, so ignore the safety-checklist bait. But the doctrine only covers the scary harm the activity is famous for. A weird sideways injury, or a super-fragile victim, takes the case back to ordinary negligence.
🧪 Question
A demolition contractor was hired to level an old parking garage in a city's warehouse district. The contractor obtained every required permit, hired a nationally certified blasting engineer, used the smallest effective explosive charges, and evacuated the area beyond the distance recommended by industry guidelines. When the charges were detonated, ground vibrations traveled farther than predicted and cracked the foundation of a bakery two blocks away. The bakery owner sued the contractor on a strict liability theory, and the evidence at trial established the facts above.
Is the bakery owner likely to prevail?
(A) No, because the contractor exercised reasonable care in every aspect of the demolition. (B) No, because the contractor complied with all applicable permits and industry guidelines. (C) Yes, because blasting is an abnormally dangerous activity and the vibration damage flowed from the risk that makes it dangerous. (D) Yes, because the doctrine of res ipsa loquitur permits an inference of negligence from foundation damage of this kind.
Answer: (C). Blasting is the textbook abnormally dangerous activity: high risk of serious harm that reasonable care cannot eliminate, and not a matter of common usage. Vibration damage to nearby structures is precisely the risk that makes blasting dangerous, so the contractor is liable despite flawless precautions.
💡 Why the Wrong Answers Are Wrong
- (A) applies a negligence standard; the entire point of strict liability is that reasonable care does not defeat the claim.
- (B) treats regulatory compliance as a defense, but permits and guidelines only bear on negligence, which the plaintiff need not prove.
- (D) reaches the right result on the wrong theory; res ipsa is a negligence inference, and no negligence showing is needed at all.
- ELI-10: The misconception is thinking careful people can't owe money. For truly risky shows, the runner pays even on a perfect day.
