Module 10 - Factual Causation

What must a plaintiff show after establishing negligent conduct?

The plaintiff must show that the conduct was the factual cause and proximate cause of their injury.

What is the general rule for factual causation?

The defendant's conduct must be the actual cause of the plaintiff's injury for liability to attach.

What is the "but for" test in factual causation?

The "but for" test determines if an act or omission was a factual cause of the injury by asking whether the injury would not have occurred "but for" the defendant's conduct.

When does the "but for" test apply?

It applies when multiple acts combine to cause the injury, but none alone would be sufficient to cause the injury.

How can a defendant refute causation under the "but for" test?

A defendant can show that the plaintiff would have been injured "even if" the defendant's negligent act or omission did not occur.

Give an example of the "but for" test.

A plaintiff falls off the defendant's boat and is pulled under by a heavy undertow. The defendant's failure to have a life preserver on board is not a factual cause of the injuries because the plaintiff would have been pulled under by the undertow even if a life preserver was present.

What is the substantial factor test in factual causation?

The substantial factor test applies when several causes contribute to the injury, and any one of them would have been sufficient to cause the injury. The defendant's conduct is a factual cause if it was a substantial factor in causing the injury.

What is an example of the substantial factor test?

Two defendants cause separate forest fires that eventually merge and destroy the plaintiff's home. Both defendants are liable because either fire alone would have been sufficient to cause the damage.

What is the unascertainable causes approach?

When there are two acts, only one of which caused the injury, but it is unclear which one, the burden shifts to the defendants to prove that their conduct was not the actual cause.

Give an example of the unascertainable causes approach.

Two defendants negligently fire shotguns in the plaintiff's direction. The plaintiff is hit by one pellet but cannot tell which defendant fired it. Both defendants must prove that the pellet was not from their gun, or they both may be held liable.

How does the merged causes approach differ from the unascertainable causes approach?

In the merged causes approach, both parties caused the harm, while in the unascertainable causes approach, only one party caused the harm, but it is unclear which one.