Strict Liability — Apply strict liability rules - Bar Exam Uniform

SECTION 1

Historical Context & Motivation

The concept of strict liability represents one of the most significant departures from the fault-based paradigm that dominated Anglo-American tort law for centuries. Under traditional negligence theory, a plaintiff must demonstrate that the defendant breached a duty of reasonable care, but strict liability dispenses with this requirement entirely, imposing liability regardless of the defendant's level of care. The doctrine arose from a recognition that certain activities, while socially useful, create risks so extraordinary that the actor should bear the costs of any resulting harm. Courts and legislatures gradually expanded this principle from its common law origins in livestock trespass to encompass abnormally dangerous activities, wild animal keeping, and ultimately products liability—reflecting a broader policy judgment about fair allocation of risk in an industrializing society.

1868 • Rylands v. Fletcher

The House of Lords established that a landowner who brings something onto their property that is likely to cause mischief if it escapes is strictly liable for resulting damages. This landmark case created the "non-natural use of land" doctrine that became foundational for strict liability in Anglo-American law.

1947 • Restatement (First) of Torts Codification

The American Law Institute formally codified strict liability principles in the Restatement (First) of Torts, distinguishing between trespass by livestock, wild animal liability, and ultrahazardous activities—providing a systematic framework adopted by courts nationwide.

1963 • Greenman v. Yuba Power Products

Justice Traynor's opinion in this California Supreme Court case established strict products liability, holding manufacturers liable for defective products regardless of privity of contract or fault, fundamentally reshaping consumer protection law.

1977 • Restatement (Second) of Torts §§ 519–520

The Restatement (Second) refined the doctrine of abnormally dangerous activities, replacing the "ultrahazardous" standard with a multi-factor balancing test that remains the prevailing framework for determining when strict liability applies to non-products claims.

1998 • Restatement (Third) of Torts: Products Liability

The ALI published the Restatement (Third), which distinguished among manufacturing defects, design defects, and failure-to-warn claims, refining the strict liability framework for products to incorporate risk-utility balancing for design defects.

The evolution of strict liability raises a persistent doctrinal question: When should society impose liability on an actor who has exercised all reasonable care? The answer lies in understanding the policy rationales—loss spreading, deterrence of abnormally risky conduct, and the internalization of externalities—that justify departing from negligence's fault-based framework. For the bar exam, you must be able to identify strict liability categories, apply the Restatement factors, and distinguish strict liability from negligence and intentional tort theories.

SECTION 2

Core Principles & Definitions

Strict liability operates on a fundamentally different axis than negligence or intentional torts. Whereas negligence evaluates the defendant's conduct against a standard of reasonableness, strict liability focuses on the nature of the activity or the condition of the product. The defendant's mental state, diligence, and level of care are irrelevant to the threshold question of liability. This does not mean that strict liability is absolute liability—important limitations such as causation requirements, scope-of-risk limitations, and certain affirmative defenses still constrain the doctrine.

Abnormally Dangerous Activities

Activities that create a foreseeable and highly significant risk of harm even when reasonable care is exercised, and that are not a matter of common usage in the community. Governed by the Restatement (Second) § 520 six-factor test.

Wild Animal Liability

Possessors of wild animals (animals ferae naturae) are strictly liable for harm caused by those animals, regardless of the precautions taken. The liability extends to harm resulting from the animal's dangerous propensities characteristic of its species.

Domestic Animal Exception

Owners of domestic animals are generally held to a negligence standard unless the owner has knowledge of the animal's dangerous propensities (the "one-bite rule"), at which point strict liability attaches to harm caused by that known propensity.

Products Liability (Manufacturing Defect)

A commercial seller is strictly liable for harm caused by a product that departs from its intended design. The plaintiff need not prove negligence in the manufacturing process—only that the product was defective when it left the defendant's control.

Scope-of-Risk Limitation

Strict liability extends only to the type of harm that makes the activity abnormally dangerous or the animal dangerous. If the harm falls outside that scope, the plaintiff must establish liability on other grounds such as negligence.

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KEY TAKEAWAY

Think of strict liability as operating like a toll road rather than a traffic court. In traffic court (negligence), the state only penalizes you if you drove carelessly. On a toll road (strict liability), you pay the toll simply because you chose to use the road—regardless of how carefully you drove. Similarly, a defendant engaged in an abnormally dangerous activity "pays the toll" of compensating injured plaintiffs simply because they chose to engage in the activity, not because they did so negligently.

SECTION 3

Visual Explanation — Strict Liability Decision Framework

This flowchart illustrates the analytical path for determining whether strict liability applies. Begin by categorizing the defendant's activity, then apply the relevant sub-test (§ 520 factors for abnormally dangerous activities, wild vs. domestic classification for animals, or defect analysis for products). Always confirm that the harm falls within the scope of risk that makes the activity or product dangerous.

The diagram above illustrates the structured analytical approach you should follow on a bar exam essay or MBE question. The critical first step is identifying the category of strict liability at issue—abnormally dangerous activity, animal keeping, or products liability. Each category has its own threshold requirements, but all three share the common feature that the defendant's level of care is irrelevant to the prima facie case. Note the scope-of-risk limitation at the bottom: strict liability does not make the defendant an insurer against all harm, only harm of the type that made the activity or product dangerous in the first place.

SECTION 4

How It Works — The Restatement § 520 Factors

The most heavily tested component of non-products strict liability on the bar exam is the Restatement (Second) of Torts § 520, which provides six factors for determining whether an activity is abnormally dangerous. Courts weigh these factors holistically; no single factor is dispositive, and not every factor need be satisfied. The analysis is inherently fact-intensive and context-dependent, making it ripe for essay examination. Courts look to the totality of circumstances, and the factors often interact—for instance, an activity may pose a high degree of risk (Factor 1) precisely because there is an inability to eliminate the risk through reasonable care (Factor 3).

The Six Factors of § 520

Factor (a): Existence of a high degree of risk of some harm. The activity must create a significant probability that harm will occur. This does not require certainty—only a meaningfully elevated risk compared to ordinary activities.
Factor (b): Likelihood that the harm will be great. Even if the probability of harm is modest, the severity of potential consequences may be enormous (e.g., storing large quantities of explosives).
Factor (c): Inability to eliminate the risk by exercise of reasonable care. This is often considered the most important factor. If the risk can be managed through ordinary precautions, negligence rather than strict liability is the appropriate standard.
Factor (d): Extent to which the activity is not a matter of common usage. Driving automobiles, though dangerous, is a matter of common usage and thus not abnormally dangerous. Blasting operations, by contrast, are not commonly undertaken by the general public.
Factor (e): Inappropriateness of the activity to the place where it is carried on. An activity may be abnormally dangerous in a residential neighborhood but perfectly acceptable in a remote industrial zone. Location is context-critical.
Factor (f): Extent to which the activity's value to the community is outweighed by its dangerous attributes. This factor introduces a cost-benefit analysis, though courts often note that an activity's social value does not immunize it from strict liability—it merely bears on the classification question.

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BAR EXAM TIP

On MBE questions, the examiners frequently test Factor (c)—the inability to eliminate risk through reasonable care—as the linchpin distinguishing strict liability from negligence. If the question states that the defendant "took every possible precaution" but harm occurred anyway, this signals a strict liability analysis. Also watch for Factor (d): if the activity is described as "common" or "ordinary," strict liability is likely inapplicable.

Activities that courts have typically classified as abnormally dangerous include blasting and demolition, storage of large quantities of flammable or toxic substances, crop dusting, and fumigation with poisonous gases. Activities that courts have generally not classified as abnormally dangerous include driving automobiles, maintaining electrical utility lines, and operating natural gas pipelines (though jurisdictions vary on these latter examples).

SECTION 5

Detailed Breakdown — Categories & Defenses

Understanding strict liability on the bar exam requires you to distinguish among the three primary categories—abnormally dangerous activities, animal keeping, and products liability—and to know which defenses are available in each context. The following diagram provides a comparative visual overview, and the table below details the elements and available defenses for each category.

This comparative diagram shows the three major categories of strict liability side by side, including their respective elements, common examples, and available defenses. Note that the "all due care" defense is unavailable in all three categories—this is the defining feature that distinguishes strict liability from negligence.

Defense	Abnormally Dangerous	Wild Animals	Products Liability
Assumption of Risk	Yes — complete bar	Yes — complete bar	Yes — complete bar
Contributory Negligence	No (majority rule)	No (majority rule)	Varies by jurisdiction
Comparative Fault	Some jurisdictions	Some jurisdictions	Most jurisdictions
Abnormal Sensitivity of Π	Yes — no liability	Generally no	Generally no
Unforeseeable Π / Trespass	Debated; some limit	Trespasser defense applies	Foreseeable user required

Availability of Defenses Across Strict Liability Categories

SECTION 6

Worked Example — Applying Strict Liability

Consider the following fact pattern, which is representative of the type of question you might encounter on the MBE or in an essay: DemoCorp operates a blasting operation in a suburban neighborhood to prepare a site for a new commercial development. Despite using state-of-the-art techniques and employing certified blasting engineers, a controlled detonation sends rock fragments onto adjacent homeowner Paula's property, damaging her roof and injuring her while she was gardening. DemoCorp argues it took every reasonable precaution and should not be held liable.

Applying Strict Liability — Blasting in a Residential Area

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Step 1 — Identify the Category

Blasting with explosives is the paradigmatic example of an abnormally dangerous activity. Courts have nearly universally classified blasting operations as subject to strict liability under Restatement (Second) § 519. This is not a products liability or animal case—it falls squarely within the abnormally dangerous activity category.

Category: Abnormally Dangerous Activity
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Step 2 — Apply the § 520 Six-Factor Test

Factor (a): Blasting creates a high degree of risk of physical harm from flying debris, ground vibration, and concussive force—clearly satisfied. Factor (b): The harm from explosives can be catastrophic, including structural damage and serious bodily injury—satisfied. Factor (c): Even with state-of-the-art techniques, blasting cannot be made entirely safe; the risk of scattered debris is inherent—this is the critical factor, and it is satisfied. Factor (d): Blasting is not a matter of common usage by the general public—satisfied. Factor (e): The blasting occurs in a suburban neighborhood, making it particularly inappropriate for the location—strongly satisfied. Factor (f): While commercial development has social value, the dangerous attributes of blasting in a residential area outweigh that value for purposes of classification—satisfied.

All six factors weigh in favor of classification as abnormally dangerous.
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Step 3 — Evaluate Causation

The blasting was the actual cause (but-for cause) of the rock fragments striking Paula's property and person. The blasting was also the proximate cause—flying debris from an explosion is a foreseeable consequence, and there are no superseding intervening causes to break the causal chain.

Both actual and proximate causation are established.
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Step 4 — Confirm Scope of Risk

The harm suffered—property damage and physical injury from flying debris—is precisely the type of harm that makes blasting an abnormally dangerous activity. If Paula had instead tripped over a blasting cap left on the sidewalk, a negligence analysis might be more appropriate, but direct concussive or projectile harm is well within the scope of risk.

Harm is within the scope of risk that makes blasting dangerous.
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Step 5 — Evaluate Defenses

DemoCorp's argument that it "took every reasonable precaution" is not a defense to strict liability—this is precisely the kind of argument strict liability forecloses. There is no evidence that Paula assumed the risk of blasting, nor does her ordinary activity of gardening constitute comparative fault that would apply even in jurisdictions recognizing that defense. No valid defense is available.

No valid defense. DemoCorp is strictly liable for Paula's injuries and property damage.

SECTION 7

Strict Liability vs. Negligence vs. Intentional Torts

One of the most common bar exam traps involves confusing strict liability with negligence or intentional tort theories. While all three are theories of tort liability, they differ fundamentally in what the plaintiff must prove and what defenses are available. The following comparison table highlights the critical distinctions you should internalize for exam day.

Element / Feature	Strict Liability	Negligence	Intentional Torts
Mental State Required	None — liability without fault	Unreasonable conduct (failure to meet standard of care)	Intent or substantial certainty of harmful contact
Focus of Analysis	Nature of the activity or product	Defendant's conduct vs. reasonable person standard	Defendant's volitional act and state of mind
"Due Care" as Defense	Not a defense	Complete defense (Δ met standard of care)	Not relevant (intent already established)
Contributory/Comparative Negligence	Generally not a defense (majority rule)	Available as defense	Generally not a defense
Scope of Liability	Limited to type of harm making activity dangerous	Foreseeable type of harm (Palsgraf)	Broader — transferred intent, eggshell plaintiff
Policy Rationale	Loss spreading; internalizing externalities	Deterring unreasonable risk creation	Punishing and deterring intentional wrongdoing

Comparison of Three Major Tort Liability Theories

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KEY TAKEAWAY

Think of the three liability theories as three different lanes on the same highway. The "intentional tort" lane requires the plaintiff to show the defendant deliberately steered into harm. The "negligence" lane requires showing the defendant was driving carelessly. The "strict liability" lane simply requires showing the defendant was driving a vehicle so inherently dangerous—say, a truck loaded with unstable nitroglycerin—that the mere choice to drive it creates liability regardless of how carefully the defendant drove. On the bar exam, always identify which lane the fact pattern directs you to before analyzing the elements.

SECTION 8

Connection to Advanced Theory — Products Liability & Restatement (Third)

While the core strict liability principles discussed above apply to abnormally dangerous activities and wild animals, the most commercially significant application of strict liability is in products liability. The Restatement (Third) of Torts: Products Liability (1998) refined the earlier Restatement (Second) § 402A framework by distinguishing among three types of product defects, each with its own analytical standard. Understanding these distinctions is essential because bar examiners frequently test the nuances of when "strict" liability in the products context actually incorporates negligence-like reasoning.

Feature	Restatement (Second) § 402A	Restatement (Third) — Products Liability
Defect Standard	Single "unreasonably dangerous" standard for all defects	Three distinct standards: manufacturing, design, and warning defects
Manufacturing Defect	True strict liability	True strict liability — product departs from intended design
Design Defect	Consumer expectations test	Risk-utility balancing (reasonable alternative design required) — resembles negligence
Failure to Warn	Subsumed under "unreasonably dangerous" standard	Reasonableness standard — what a reasonable manufacturer would warn about
Who Is Liable?	"One who sells" — commercial sellers in chain of distribution	Same scope — commercial sellers, including retailers, wholesalers, and manufacturers

Evolution from Restatement (Second) to Restatement (Third) Products Liability

The critical insight for bar exam purposes is that only manufacturing defects remain truly "strict" under the Restatement (Third). Design defects and failure-to-warn claims under the Third Restatement incorporate reasonableness analysis, blurring the line between strict liability and negligence. Many jurisdictions continue to apply the Restatement (Second) consumer expectations test for design defects, while others have adopted the Third Restatement's risk-utility approach. Be prepared to identify which framework applies and to articulate the differences. Additionally, note that strict liability in the products context extends to all commercial sellers in the chain of distribution—manufacturers, distributors, wholesalers, and retailers—even if the retail seller had no opportunity to inspect the product. Casual or occasional sellers (e.g., a neighbor selling a used lawnmower) are not subject to strict products liability.

SECTION 9

Practice Problems

Question 1: CONCEPTUAL

A farmer keeps bees on her rural property to produce honey. One of her hives swarms and the bees sting a neighbor's child, causing serious allergic reaction injuries. The farmer exercised all reasonable precautions in maintaining her hives. Under the Restatement approach, should the farmer be held strictly liable for the child's injuries? Explain your reasoning, addressing whether bees are classified as wild or domestic animals.

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Under the Restatement approach, bees are generally classified as wild animals (ferae naturae), not domestic animals, because they have not been domesticated to the degree of dogs, cats, or livestock and retain inherently dangerous propensities (stinging). As possessors of wild animals, beekeepers are strictly liable for harm caused by the bees' dangerous propensities—here, stinging—regardless of the precautions taken. The farmer's exercise of all reasonable care is irrelevant to a strict liability analysis. The child's allergic reaction is the type of harm that makes bees dangerous (their sting), so the harm falls within the scope of risk. However, some jurisdictions (particularly those with significant agricultural beekeeping) have classified bees as domestic animals, in which case the farmer would be liable only under a negligence standard unless she had prior knowledge of unusually aggressive hive behavior.

Question 2: BASIC APPLICATION

A construction company uses dynamite to remove large rock formations from a building site located two miles from the nearest residence. The company follows all applicable safety regulations and employs licensed blasting professionals. A concussive wave from a detonation cracks the foundation of a distant homeowner's house. Apply the § 520 six-factor test and determine whether the construction company is strictly liable.

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Factor (a): Dynamite blasting creates a high degree of risk of harm—satisfied. Factor (b): The potential severity of harm from explosives is great, including structural damage and physical injury—satisfied. Factor (c): Concussive waves from blasting cannot be completely eliminated through reasonable care, even with licensed professionals and safety protocols—satisfied (this is the key factor). Factor (d): Using dynamite is not a matter of common usage by the general public—satisfied. Factor (e): The site is two miles from the nearest residence, which weakens this factor compared to suburban blasting; however, the fact that harm reached the residence demonstrates the activity's reach—modestly satisfied. Factor (f): While construction has social utility, the dangerous attributes of blasting still outweigh that value for classification purposes. On balance, the factors strongly support classification as an abnormally dangerous activity, and the company is strictly liable for the foundation damage regardless of its compliance with safety regulations.

Question 3: INTERMEDIATE

Diana keeps a pet chimpanzee named Max in her suburban home. Max has never shown aggressive behavior. One day, Max escapes from his enclosure, runs into a neighbor's yard, and knocks over an elderly neighbor, breaking her hip. Diana argues that because Max had no history of violence, she should be held to a negligence standard under the "one-bite rule." Evaluate Diana's argument and determine the appropriate liability standard.

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Diana's argument fails. The "one-bite rule" applies only to domestic animals—animals that, as a species, have been domesticated and are not typically dangerous. Chimpanzees are wild animals (ferae naturae) regardless of how long they have been kept in captivity or how docile an individual animal appears. Under the Restatement approach, a possessor of a wild animal is strictly liable for harm caused by the animal's dangerous propensities, and courts attribute to wild animals the dangerous propensities characteristic of their species, not just the known propensities of the individual animal. Chimpanzees are known to possess extraordinary strength and the potential for unpredictable aggressive behavior. The fact that Max had no prior history of aggression is irrelevant—strict liability for wild animals does not require prior knowledge of dangerous propensities. Diana is strictly liable for the neighbor's broken hip.

Question 4: APPLIED

ChemStore, Inc. operates a large chemical storage facility in an industrial park. The facility stores thousands of gallons of hydrochloric acid in state-of-the-art containment systems. Due to an unforeseeable earthquake—the first seismic event in the region in 200 years—several storage tanks rupture, releasing acid that flows into a nearby creek and contaminates the water supply of a downstream residential community. Residents suffer property damage and health effects. ChemStore argues it should not be strictly liable because the earthquake was an unforeseeable Act of God. Analyze ChemStore's liability, addressing both the strict liability classification and the Act of God defense.

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First, storing large quantities of hydrochloric acid is very likely an abnormally dangerous activity under § 520. The activity creates a high degree of risk (Factor a), the potential harm is severe including environmental contamination and health effects (Factor b), even state-of-the-art containment cannot eliminate the risk of catastrophic failure (Factor c), bulk toxic chemical storage is not common usage (Factor d), and proximity to a water supply and residential area makes the location somewhat inappropriate (Factor e). Regarding ChemStore's Act of God defense, the Restatement position is nuanced. Under § 522, a defendant engaged in an abnormally dangerous activity is liable even when harm is caused by the unexpected operation of a force of nature, so long as the harm results from the kind of risk that makes the activity abnormally dangerous. Here, the risk of acid release and environmental contamination is precisely what makes bulk acid storage dangerous. While the earthquake was the triggering event, it was the stored acid—not the earthquake itself—that caused the downstream harm. Most courts would hold that the Act of God defense does not apply because the abnormally dangerous activity created the very risk that materialized, even if the triggering mechanism was unforeseeable. ChemStore is likely strictly liable.

Question 5: CRITICAL THINKING

Consider two adjacent landowners: Alpha operates a fireworks manufacturing facility, and Beta runs a daycare center. A fire at Alpha's facility causes stored fireworks to detonate, sending debris onto Beta's property and injuring several children. Beta sues Alpha under strict liability. Alpha counterclaims that Beta is comparatively at fault for operating a daycare center next to a fireworks factory. Separately, one of the injured children's parents (Gamma) had signed a waiver acknowledging that the daycare was located near a fireworks facility and "accepting all associated risks." Analyze: (1) Alpha's strict liability for the abnormally dangerous activity, (2) whether Beta's comparative fault in choosing the location is a valid defense, and (3) whether Gamma's waiver constitutes assumption of risk barring recovery on behalf of the child.

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Issue (1): Fireworks manufacturing is a classic abnormally dangerous activity satisfying all six § 520 factors—high risk of explosion, catastrophic potential harm, inability to eliminate risk through care, uncommon usage, inappropriate location near a daycare, and dangerous attributes outweighing social value at this location. Alpha is strictly liable. Issue (2): Under the majority rule, ordinary contributory or comparative negligence of the plaintiff is not a defense to strict liability for abnormally dangerous activities. Beta's decision to locate a daycare near a fireworks factory may seem unwise, but it does not constitute the kind of voluntary assumption of risk that would bar recovery. Even in jurisdictions that apply comparative fault to strict liability claims, Beta's location choice would likely be assessed as a relatively minor allocation compared to Alpha's operation of the dangerous activity. Issue (3): The waiver signed by Gamma raises assumption of risk, which is generally available as a defense in strict liability cases. However, courts would likely find the waiver unenforceable on public policy grounds for several reasons: (a) a parent generally cannot waive the tort rights of a minor child; (b) even if the parent could consent for themselves, the waiver's enforceability against claims for physical injury (as opposed to property damage) is disfavored; and (c) the waiver was executed in the context of a childcare contract, where there is often unequal bargaining power. Most courts would not allow this waiver to bar the child's recovery.

SUMMARY

Summary — Strict Liability Rules

Summary

Strict liability imposes liability without fault in three primary categories: abnormally dangerous activities (analyzed under the Restatement (Second) § 520 six-factor test), wild animal keeping (where the possessor is liable for harm from the animal's dangerous propensities regardless of precautions), and products liability (where commercial sellers are liable for defective products, with manufacturing defects judged by true strict liability and design defects increasingly subject to risk-utility balancing under the Restatement (Third)). The defendant's exercise of reasonable care is never a defense to a strict liability claim.

Critical limitations apply: strict liability extends only to harm within the scope of risk that makes the activity or product dangerous, and assumption of risk remains a valid defense across all categories. Contributory negligence is generally not a defense under the majority rule, though comparative fault is applied in some jurisdictions, particularly in products cases. On the bar exam, always begin by identifying the strict liability category, apply the relevant analytical framework, confirm that the harm falls within the scope of risk, and then evaluate available defenses.