T10 Factual Cause Flashcards
CAUSATION generally
Once negligent conduct is shown (a breach of the standard of care owed a foreseeable plaintiff), the plaintiff must show that the conduct was the cause of their injury.
For liability to attach, the plaintiff must show BOTH FACTUAL cause (actual cause) (cause-in-fact) and PROXIMATE cause.
Factual Causation:
Rule:
Tests?
factual cause (actual cause)
Link between breach and harm.
General rule: Use But-For test
Merged Causes: Substantial Factor test
Unascertainable cause: Shift Burden of proof.
Several tests exist for determining if the defendant’s conduct is a factual cause of the plaintiff’s injury.
1. But For test
2. Merged causes - substantial factor test
3. Unascertainable causes approach
“BUT FOR” TEST
Injury would not have occured “but for” act or omission.
Can be multiple - q is whether breach is A BUT-FOR CAUSE, not the only but-for cause.
Defendant’s rebuttal to but-for is always “EVEN IF”
An act or omission is a factual cause of an injury when the injury would not have occurred “but for” the act or omission.
This test applies where several acts (each insufficient to cause the injury alone) combine to cause the injury.
A D can refute this by showing that the plaintiff would have still been injured “even if” the act or omission did not occur.
MERGED CAUSES—SUBSTANTIAL FACTOR TEST…
Multiple Defendants: Merged Causes
Merged causation: 2 Ds acting independently each commit a breach combining into a single indivisible harm
(Ex: two negligently set fires). Apply when BOTH parties caused the harm.
If 2 defendants + 2 breaches + Merged causation…
USE SUBSTANTIAL FACTOR test instead of “but-for” test.
Substantial factor Test: D liable if breach contributed in significant/substnatial way to ultimate jury.
BUT, if breach would have been able to cause entire harm if it had been the only breach, it IS a substantial factor.
Where several causes bring about injury, and any one alone would have been sufficient to cause the injury, the defendant’s conduct is the cause in fact if it was a substantial factor in causing the injury.
Some courts refer to this situation as one involving “multiple sufficient causes.”
D1 throws a lit cigarette out of a car window starting a forest fire. At the same time D2 fails to properly extinguish a campfire starting a second forest fire. The two fires spread, eventually join together, and burn down P’s house.
RESULT?
SUBSTANTIAL FACTOR TEST APPLIES:
D1 and D2 are jointly and severally liable and P can recover the full amount of damages from either defendant.
UNASCERTAINABLE CAUSES APPROACH
2 acts, only one of which causes injury, but unkown which one.
(Ex: Hunting accident, both shoot but P only hit once).
Unascertainable cause SHIFTS BURDEN OF PROOF to defendants. If neither can meet burden, we hold them jointly liable.
This test applies when there are two acts, only one of which causes injury, but it is not known which one. The burden of proof shifts to defendants, and each must show that his negligence is not the actual cause. [Summers v. Tice]
Under the unascertainable causes approach, although both parties acted negligently, ONLY ONE caused the harm.
D1 and D2 both negligently fire shotguns in P’s direction. P is hit by one pellet, but cannot tell which gun fired the shot.
RESULT?
D1 and D2 will have to prove that the pellet was not theirs. If unable to do this, they may both be liable.
Distinguish SUBSTANTIAL FACTOR vs UNASCERTAINABLE CAUSES
Under the merged causes approach, both parties caused the harm.
Under the unascertainable causes approach, although both parties acted negligently, only one caused the harm.
