Torts
Actual Cause (Cause-in-Fact)
Definition
Actual cause, or cause-in-fact, establishes the factual link between the defendant's conduct and the plaintiff's injury. The standard test is the but-for test: but for the defendant's negligence, would the harm have occurred? When multiple actors contribute to an indivisible injury and the but-for test fails, courts may apply the substantial factor test. The burden of proof is on the plaintiff to establish actual causation by a preponderance of the evidence.
Example
Two hunters negligently fire simultaneously, and one pellet hits the plaintiff. Because neither can prove who fired the injuring shot, the court may shift the burden under alternative liability.