Causation in Negligence

Flashcards for reviewing the concepts of cause in fact, including the but-for test, substantial factor test, and unascertainable causes approach.

Cause in Fact

One of two parts of causation (the other being proximate cause); requires the plaintiff to show that the harm they suffered was caused by the defendant's negligent act.

But For Test

A test for proving causation where the injury would not have occurred but for the defendant's negligent act.

Substantial Factor Test

A test used when several causes merge to bring about a single injury; asks whether the defendant's negligence was a substantial factor in causing the injury.

Unascertainable Causes/Alternative Cause Approach

An approach where the burden of proof shifts to the defendants to prove that their negligence did not cause the injury when the plaintiff can prove both were negligent, but it can't be determined which defendant's negligence caused the injury.

Summers v. Tice

Classic example of the unascertainable causes approach where two hunters negligently fired their shotguns, and it was impossible to determine whose shot injured the plaintiff; court shifted the burden of proof to the defendants.

Enterprise Liability

An extension of the unascertainable causes approach, applied to industry groups where multiple manufacturers produce the same product; manufacturers can be held liable proportional to their share of the market.