Legal Causation Causality Study Group Erica Beecher-Monas University

Legal Causation Causality Study Group Erica Beecher-Monas University of Arkansas at Little Rock School of Law March 23, 2000 © Erica Beecher- Monas 1

Definitions and Purposes n Legal Problems Are Disputes – Someone is Injured n The Legal Questions – Who’s Responsible? n Did the defendant’s act/ omission cause harm? – How Much Responsibility? n Causal nexus may determine extent of liability – Legal Causation is an element of responsibility n But causation is not responsibility 2

Causation in Torts n Did A’s breach of a duty owed to B cause B’s harm? – Causation determines liability – Causation may also determine the extent of liability n Limited by “remoteness” or proximate cause 3

Causation in Criminal Law n Criminal law defines offense as intentional act causing specific harm – causal nexus required – proof “beyond reasonable doubt” n Purpose: deterrence, retribution 4

Causation in Contract Law n In contract law, causation is the causal nexus between breach of contract and damages – Causal question will determine extent of liability – Limited by foreseeability – Purpose: efficient use of resources 5

Cause in Fact n Material Cause – Is A’s act a necessary condition for B’s harm? – Fact question n n (for the jury) But-For Test: Would the harm have occurred w/o A’s act? – Use of contra-factual reasoning n Must refer to “normal” conditions 6

But-For Causation n Temporal Sequence: Cause Precedes Effect – B’s harm follows A’s act in sequence w/o intervening forces n Counterfactual Inference: Absent A, Would B happen? – Involves judgment about normal conditions 7

Jury Instruction Cause which in natural and continuous sequence, n unbroken by any efficient intervening cause, n produced the injury and n without which the injury would not have occurred n 8

Legal Concerns About Causation Causes n Mere conditions n Factors that break the chain n 9

Conditions n Sufficient Conditions n Cause is one of a set of conditions jointly sufficient to produce the consequences – Is B’s fire damage caused by A’s dropping stillburning cigarette butt into trash? n Fire (that damaged B’s property) would not have occurred in the trash absent each of n A’s act (dropping lit butt) n Oxygen n Flammable trash 10

Cause n Necessary Condition – Cause is that condition necessary to complete the set n Fire could not have occurred absent A’s butt n The other factors are “mere conditions” 11

Simultaneous Acts n What happens w/ more than one cause? n. A and C simultaneously shoot B in the brain – Either shooting is a necessary condition (cause) of B’s death n But-for test isn’t satisfied – Court must make value judgment on responsibility 12

Multiple Causation n Multiple Causation: If there are 2 causes, treat each as cause? n. A poisons B and before poison takes effect C shoots B in brain n Each cause is sufficient to produce B’s death Mode of injury determines causal nexus But what if death was nanoseconds before bullet would have killed B? 13

Substantial Factor n Substantial factor: ordinarily the result doesn’t occur without it – Whether harm is a consequence of the wrongful act given 3 rd factor? n Normal physical events subsequent to wrongful act do not relieve wrongdoer of responsibility n Abnormal conjunction of wrongful act + 3 rd factor cancels causal nexus n As long as conjunction is not designed 14

Intervening Events n Abnormal conjunction of wrongful act and 3 rd factor – Extraordinary acts of nature n If A poisons B & on way to hospital B is struck by lightning – No liability for murder even though “but for” causation – Extraordinary coincidence n A RR negligently carries B beyond her destination, puts her up in a hotel, where a lamp explodes in her room – Ct holds RR negligence was not substantial factor n i. e. hotel lamp explosion was an intervening event n Coincidence may not be intended 15

Subsequent Events n If subsequent event would not occur absent A’s act, A is liable n. A negligently drives engine over RR w/ crossing in 2 places – Just before colliding A shut off steam (to stop engine) – Collision forced open throttle – Engine went backwards, hitting B’s train 2 d time – Liability? 16

Abnormal Circumstances n Abnormal circumstances at time of wrongful act do not cancel causation – Eggshell skull n. A negligently drops book from ladder on B’s head causing B’s death tho normal result would have been harmless – Taking the plaintiff as you find her n. A runs over (and kills) fatally ill (but not yet dead) B n A is liable for B’s death 17

Substantial Factor is Controversial n Courts disagree over the meaning of both “substantial” and “factor” – Boat owner fails to maintain hold or vent it, so gas built up in hold n Boat struck by lightning and blew up – One ct held lighting was intervening cause – Other ct held owner’s negligence was substantial factor 18

Increasing the Risk of Harm n Dr. A negligently prescribes drug for B who is already terminally ill – B dies – Unclear if B’s death is from drug or illness n 3 Major Approaches – Reverse burden of proof to A to disprove causation – Infer causation – Hold A liable for extent of increased risk 19

Lost Chance Cases n Usually medical malpractice cases – If there was a substantial chance that B would survive and A destroyed that chance, A is liable n A’s liability stems from increasing the risk of the particular harm that B suffered – Dr. A’s negligently performed surgery on B, a diabetic w/ complications, caused B to go blind at the same time as B suffered a stroke which would have caused her blindness n Court by-passed the but-for test, finding both were independent and equally plausible causes n Court inferred causation from A’s act increasing B’s risk 20

R 2 d of Torts Substantial Factor Test n How many factors other than defendant A’s act contribute to plaintiff B’s harm? – Did A’s conduct create a force in continuous and active operation up to the time of the harm? n Did A’s conduct create a situation harmless unless acted on by other forces? n How much time lapsed between A’s act and 21 B’s harm?

Zone of Risk n Subsequent intervening acts – A will be liable if act is w/in zone of risk created by A’s act n. A leaves B’s house unlocked n C steals B’s stuff – A is liable for B’s loss because theft is a common result of leaving the house unlocked n “natural consequences” 22

Comparative Fault n A is not wholly responsible for B’s harm – Even if A’s risk-creating act is not sole cause of the harm, A may be liable for a % of the harm n Joint tortfeasors – A and C both collide with B n Contributory negligence – A and B are both driving negligently when they collide n If B can show what % of her harm was caused by A’s act n Or if A can show what % of the harm would have been prevented had B taken precautions 23

Market Share Liability n B gets cancer from DES administered to her mother while in utero – B can show that DES caused her cancer – B cannot show who produced the DES that her mother received n Ct permitted B to sue any manufacturer who had substantial market share in DES at the time B’s mother ingested it n Defendant will be liable for % of its market share 24

Toxic Torts n General causation – whether substance is capable of causing particular injury or condition in general population n Expert n testimony by researcher specific causation – whether substance caused particular individual's injury – Expert testimony by medical clinician 25

Limiting Factors n Proximate Cause – Policy determination re: how far to extend liability n Foreseeability – Based on the idea of “normal” conditions 26

Proximate Cause n Policy Question: Is there any legal reason to preclude treating A’s act as the cause of B’s injury? – Palsgraf n Idea of remote causes difficult to foresee – Natural and Probable Consequences Test n Was B’s injury the natural and probable consequence of A’s act? 27

Functions of Judge and Jury in Determining Causation n Jury decides questions of fact (like causation) – But if reasonable minds could not differ on the issue, the judge decides n Judge decides questions of law – whethere is sufficient evidence – scope of rules – types of damage for which law provides a remedy – allocation of risks 28

Framing the But-For Question n Judge Must – Identify the injury – Identify the wrongful conduct – Create counterfactual n n Jury Question: – Would B’s injuries still have occurred if A had behaved w/in the bounds of law? what would have happened if A’s conduct had complied w/ law? 29

Evidence of Causation n Simple cases can be established by lay witnesses – A negligently broke B’s teapot n A, n B, eyewitness testimony Most require expert testimony – Standards for expertise – Standards for scientific validity 30

Burdens of Proof n Plaintiff has the burden of providing sufficient evidence to establish – Existence of causal connection n Defendant has b/p on defenses – Contributory & comparative negligence – Alternative cause 31

Contemporary Causation Issues in the Courts Multiple Causation n Ambiguous Causation n Evidence of Causation n – Use of scientific experts to prove causation – Proof by a preponderance that the evidence is scientifically valid 32

Common Sense or Policy? Hart & Honore say it’s all just common sense (in 497 pages) n Legal realists say it’s all policy n – Courts are always influenced by law’s objectives n Judith Jarvis Thompson says “common sense” is political 33