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Legal Causation Legal Causation

Causality Study GroupCausality Study GroupErica Beecher-MonasErica Beecher-MonasUniversity of Arkansas at Little Rock University of Arkansas at Little Rock School of LawSchool of LawMarch 23, 2000March 23, 2000© Erica Beecher-Monas© Erica Beecher-Monas

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Definitions and Definitions and PurposesPurposes Legal Problems Are DisputesLegal Problems Are Disputes

– Someone is InjuredSomeone is Injured The Legal QuestionsThe Legal Questions

– Who’s Responsible?Who’s Responsible? Did the defendant’s act/ omission cause Did the defendant’s act/ omission cause

harm?harm?– How Much Responsibility?How Much Responsibility?

Causal nexus may determine extent of Causal nexus may determine extent of liabilityliability

– Legal Causation is an element of Legal Causation is an element of responsibilityresponsibility But causation is not responsibilityBut causation is not responsibility

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Causation in TortsCausation in Torts

Did A’s breach of a duty owed to Did A’s breach of a duty owed to B cause B’s harm?B cause B’s harm?– Causation determines liabilityCausation determines liability– Causation may also determine the Causation may also determine the

extent of liabilityextent of liability Limited by “remoteness” or proximate Limited by “remoteness” or proximate

causecause

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Causation in Criminal Causation in Criminal LawLaw Criminal law defines offense as Criminal law defines offense as

intentional act causing specific intentional act causing specific harmharm– causal nexus requiredcausal nexus required– proof “beyond reasonable doubt”proof “beyond reasonable doubt”

Purpose: deterrence, retributionPurpose: deterrence, retribution

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Causation in Contract Causation in Contract LawLaw In contract law, causation is the In contract law, causation is the

causal nexus between breach of causal nexus between breach of contract and damagescontract and damages– Causal question will determine Causal question will determine

extent of liabilityextent of liability– Limited by foreseeabilityLimited by foreseeability– Purpose: efficient use of resourcesPurpose: efficient use of resources

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Cause in FactCause in Fact

Material CauseMaterial Cause– Is A’s act a necessary condition for B’s Is A’s act a necessary condition for B’s

harm?harm?– Fact questionFact question

(for the jury)(for the jury)

But-For Test: Would the harm have But-For Test: Would the harm have occurred w/o A’s act?occurred w/o A’s act?– Use of contra-factual reasoningUse of contra-factual reasoning

Must refer to “normal” conditionsMust refer to “normal” conditions

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But-For CausationBut-For Causation

Temporal Sequence: Cause Temporal Sequence: Cause Precedes EffectPrecedes Effect– B’s harm follows A’s act in B’s harm follows A’s act in

sequence w/o intervening forcessequence w/o intervening forces Counterfactual Inference: Absent Counterfactual Inference: Absent

A, Would B happen?A, Would B happen?– Involves judgment about normal Involves judgment about normal

conditionsconditions

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Jury InstructionJury Instruction

Cause which in natural and Cause which in natural and continuous sequence,continuous sequence,

unbroken by any efficient unbroken by any efficient intervening cause, intervening cause,

produced the injury and produced the injury and without which the injury would without which the injury would

not have occurrednot have occurred

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Legal Concerns About Legal Concerns About CausationCausation CausesCauses Mere conditionsMere conditions Factors that break the chainFactors that break the chain

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ConditionsConditions

Sufficient ConditionsSufficient Conditions Cause is one of a set of conditions jointly Cause is one of a set of conditions jointly

sufficient to produce the consequencessufficient to produce the consequences– Is B’s fire damage caused by A’s dropping still-Is B’s fire damage caused by A’s dropping still-

burning cigarette butt into trash?burning cigarette butt into trash? Fire (that damaged B’s property) would not Fire (that damaged B’s property) would not

have occurred in the trash absent each of have occurred in the trash absent each of A’s act (dropping lit butt)A’s act (dropping lit butt) OxygenOxygen Flammable trashFlammable trash

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CauseCause

Necessary ConditionNecessary Condition– Cause is that condition necessary Cause is that condition necessary

to complete the setto complete the set Fire could not have occurred absent A’s Fire could not have occurred absent A’s

buttbutt The other factors are “mere conditions”The other factors are “mere conditions”

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Simultaneous ActsSimultaneous Acts

What happens w/ more than one What happens w/ more than one cause?cause?

A and C simultaneously shoot B in the A and C simultaneously shoot B in the brainbrain

– Either shooting is a necessary Either shooting is a necessary condition (cause) of B’s deathcondition (cause) of B’s death But-for test isn’t satisfiedBut-for test isn’t satisfied

– Court must make value judgment on Court must make value judgment on responsibilityresponsibility

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Multiple CausationMultiple Causation

Multiple Causation: If there are 2 Multiple Causation: If there are 2 causes, treat each as cause?causes, treat each as cause?

A poisons B and before poison takes A poisons B and before poison takes effect C shoots B in braineffect C shoots B in brain

Each cause is sufficient to produce B’s Each cause is sufficient to produce B’s deathdeath

Mode of injury determines causal nexusMode of injury determines causal nexus But what if death was nanoseconds But what if death was nanoseconds

before bullet would have killed B?before bullet would have killed B?

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Substantial Factor Substantial Factor

Substantial factor: ordinarily the Substantial factor: ordinarily the result doesn’t occur without itresult doesn’t occur without it– Whether harm is a consequence of Whether harm is a consequence of

the wrongful act given 3the wrongful act given 3rdrd factor? factor? Normal physical events subsequent to Normal physical events subsequent to

wrongful act do not relieve wrongdoer of wrongful act do not relieve wrongdoer of responsibilityresponsibility

Abnormal conjunction of wrongful act + 3Abnormal conjunction of wrongful act + 3rdrd factor cancels causal nexusfactor cancels causal nexus

As long as conjunction is not designed As long as conjunction is not designed

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Intervening EventsIntervening Events

Abnormal conjunction of wrongful act and Abnormal conjunction of wrongful act and 33rdrd factor factor– Extraordinary acts of natureExtraordinary acts of nature

If A poisons B & on way to hospital B is struck by If A poisons B & on way to hospital B is struck by lightninglightning

– No liability for murder even though “but for” causationNo liability for murder even though “but for” causation

– Extraordinary coincidenceExtraordinary coincidence A RR negligently carries B beyond her A RR negligently carries B beyond her

destination, puts her up in a hotel, where a lamp destination, puts her up in a hotel, where a lamp explodes in her roomexplodes in her room

– Ct holds RR negligence was not substantial factorCt holds RR negligence was not substantial factor i.e. hotel lamp explosion was an intervening eventi.e. hotel lamp explosion was an intervening event Coincidence may not be intendedCoincidence may not be intended

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Subsequent EventsSubsequent Events

If subsequent event would not If subsequent event would not occur absent A’s act, A is liableoccur absent A’s act, A is liable

A negligently drives engine over RR w/ A negligently drives engine over RR w/ crossing in 2 placescrossing in 2 places

– Just before colliding A shut off steam (to stop Just before colliding A shut off steam (to stop engine)engine)

– Collision forced open throttleCollision forced open throttle– Engine went backwards, hitting B’s train 2d Engine went backwards, hitting B’s train 2d

timetime– Liability?Liability?

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Abnormal Abnormal CircumstancesCircumstances Abnormal circumstances at time of Abnormal circumstances at time of

wrongful act do not cancel causationwrongful act do not cancel causation– Eggshell skullEggshell skull

A negligently drops book from ladder on B’s A negligently drops book from ladder on B’s head causing B’s death tho normal result head causing B’s death tho normal result would have been harmlesswould have been harmless

– Taking the plaintiff as you find herTaking the plaintiff as you find her A runs over (and kills) fatally ill (but not yet A runs over (and kills) fatally ill (but not yet

dead) Bdead) B A is liable for B’s deathA is liable for B’s death

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Substantial Factor is Substantial Factor is ControversialControversial Courts disagree over the meaning Courts disagree over the meaning

of both “substantial” and “factor”of both “substantial” and “factor”– Boat owner fails to maintain hold or Boat owner fails to maintain hold or

vent it, so gas built up in holdvent it, so gas built up in hold Boat struck by lightning and blew upBoat struck by lightning and blew up

– One ct held lighting was intervening causeOne ct held lighting was intervening cause– Other ct held owner’s negligence was Other ct held owner’s negligence was

substantial factorsubstantial factor

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Increasing the Risk of Increasing the Risk of HarmHarm Dr. A negligently prescribes drug for Dr. A negligently prescribes drug for

B who is already terminally illB who is already terminally ill– B diesB dies– Unclear if B’s death is from drug or Unclear if B’s death is from drug or

illnessillness 3 Major Approaches3 Major Approaches

– Reverse burden of proof to A to disprove Reverse burden of proof to A to disprove causationcausation

– Infer causationInfer causation– Hold A liable for extent of increased riskHold A liable for extent of increased risk

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Lost Chance Cases Lost Chance Cases

Usually medical malpractice casesUsually medical malpractice cases– If there was a substantial chance that B would If there was a substantial chance that B would

survive and A destroyed that chance, A is liablesurvive and A destroyed that chance, A is liable A’s liability stems from increasing the risk of the A’s liability stems from increasing the risk of the

particular harm that B sufferedparticular harm that B suffered– Dr. A’s negligently performed surgery on B, a diabetic Dr. A’s negligently performed surgery on B, a diabetic

w/ complications, caused B to go blind at the same time w/ complications, caused B to go blind at the same time as B suffered a stroke which would have caused her as B suffered a stroke which would have caused her blindnessblindness

Court by-passed the but-for test, finding both were Court by-passed the but-for test, finding both were independent and equally plausible causesindependent and equally plausible causes

Court inferred causation from A’s act increasing B’s Court inferred causation from A’s act increasing B’s riskrisk

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R2d of Torts R2d of Torts Substantial Factor Substantial Factor TestTest How many factors other than How many factors other than

defendant A’s act contribute to defendant A’s act contribute to plaintiff B’s harm?plaintiff B’s harm?– Did A’s conduct create a force in Did A’s conduct create a force in

continuous and active operation up to continuous and active operation up to the time of the harm?the time of the harm?

Did A’s conduct create a situation harmless Did A’s conduct create a situation harmless unless acted on by other forces?unless acted on by other forces?

How much time lapsed between A’s act How much time lapsed between A’s act and B’s harm?and B’s harm?

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Zone of RiskZone of Risk

Subsequent intervening acts Subsequent intervening acts – A will be liable if act is w/in zone of A will be liable if act is w/in zone of

risk created by A’s actrisk created by A’s act A leaves B’s house unlockedA leaves B’s house unlocked C steals B’s stuffC steals B’s stuff

– A is liable for B’s loss because theft is a A is liable for B’s loss because theft is a common result of leaving the house common result of leaving the house unlockedunlocked

““natural consequences”natural consequences”

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Comparative FaultComparative Fault

A is not wholly responsible for B’s harmA is not wholly responsible for B’s harm– Even if A’s risk-creating act is not sole cause Even if A’s risk-creating act is not sole cause

of the harm, A may be liable for a % of the of the harm, A may be liable for a % of the harmharm

Joint tortfeasorsJoint tortfeasors– A and C both collide with BA and C both collide with B

Contributory negligenceContributory negligence– A and B are both driving negligently when they collideA and B are both driving negligently when they collide

If B can show what % of her harm was caused by If B can show what % of her harm was caused by A’s actA’s act

Or if A can show what % of the harm would have Or if A can show what % of the harm would have been prevented had B taken precautionsbeen prevented had B taken precautions

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Market Share LiabilityMarket Share Liability

B gets cancer from DES administered B gets cancer from DES administered to her mother while in uteroto her mother while in utero– B can show that DES caused her cancerB can show that DES caused her cancer– B cannot show who produced the DES B cannot show who produced the DES

that her mother receivedthat her mother received Ct permitted B to sue any manufacturer who Ct permitted B to sue any manufacturer who

had substantial market share in DES at the had substantial market share in DES at the time B’s mother ingested ittime B’s mother ingested it

Defendant will be liable for % of its market Defendant will be liable for % of its market shareshare

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Toxic TortsToxic Torts

General causation General causation – whether substance is capable of whether substance is capable of

causing particular injury or condition causing particular injury or condition in general populationin general population Expert testimony by researcher Expert testimony by researcher

specific causation specific causation – whether substance caused particular whether substance caused particular

individual's injuryindividual's injury– Expert testimony by medical clinicianExpert testimony by medical clinician

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Limiting FactorsLimiting Factors

Proximate CauseProximate Cause– Policy determination re: how far to Policy determination re: how far to

extend liabilityextend liability ForeseeabilityForeseeability

– Based on the idea of “normal” Based on the idea of “normal” conditionsconditions

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Proximate CauseProximate Cause

Policy Question: Is there any legal Policy Question: Is there any legal reason to preclude treating A’s act reason to preclude treating A’s act as the cause of B’s injury?as the cause of B’s injury?– Palsgraf Palsgraf

Idea of remote causes difficult to foreseeIdea of remote causes difficult to foresee

– Natural and Probable Consequences Natural and Probable Consequences TestTest Was B’s injury the natural and probable Was B’s injury the natural and probable

consequence of A’s act?consequence of A’s act?

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Functions of Judge and Functions of Judge and Jury in Determining Jury in Determining CausationCausation

JuryJury decides decides questions of fact questions of fact (like causation)(like causation)– But if reasonable But if reasonable

minds could not minds could not differ on the issue, differ on the issue, the judge decidesthe judge decides

JudgeJudge decides decides questions of lawquestions of law– whether there is whether there is

sufficient evidencesufficient evidence– scope of rulesscope of rules– types of damage types of damage

for which law for which law provides a remedy provides a remedy

– allocation of risksallocation of risks

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Framing the But-For Framing the But-For QuestionQuestion JudgeJudge Must Must

– Identify the injuryIdentify the injury– Identify the Identify the

wrongful conductwrongful conduct– Create counter-Create counter-

factual factual what would have what would have

happened if A’s happened if A’s conduct had conduct had complied w/ law?complied w/ law?

JuryJury Question: Question:– Would B’s Would B’s

injuries still have injuries still have occurred if A had occurred if A had behaved w/in the behaved w/in the bounds of law?bounds of law?

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Evidence of CausationEvidence of Causation

Simple cases can be established Simple cases can be established by lay witnessesby lay witnesses– A negligently broke B’s teapotA negligently broke B’s teapot

A, B, eyewitness testimonyA, B, eyewitness testimony

Most require expert testimony Most require expert testimony – Standards for expertiseStandards for expertise– Standards for scientific validityStandards for scientific validity

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Burdens of ProofBurdens of Proof

Plaintiff has the burden of Plaintiff has the burden of providing sufficient evidence to providing sufficient evidence to establishestablish– Existence of causal connectionExistence of causal connection

Defendant has b/p on defensesDefendant has b/p on defenses– Contributory & comparative Contributory & comparative

negligencenegligence– Alternative causeAlternative cause

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Contemporary Contemporary Causation Issues in the Causation Issues in the CourtsCourts

Multiple CausationMultiple Causation Ambiguous CausationAmbiguous Causation Evidence of CausationEvidence of Causation

– Use of scientific experts to prove Use of scientific experts to prove causationcausation

– Proof by a preponderance that the Proof by a preponderance that the evidence is scientifically validevidence is scientifically valid

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Common Sense or Common Sense or Policy?Policy?

Hart & Honore say it’s all just Hart & Honore say it’s all just common sense (in 497 pages)common sense (in 497 pages)

Legal realists say it’s all policyLegal realists say it’s all policy– Courts are always influenced by Courts are always influenced by

law’s objectiveslaw’s objectives Judith Jarvis Thompson says Judith Jarvis Thompson says

“common sense” is political“common sense” is political