Causation in Negligence

Causation in Negligence

Causation is a critical and often complex element of a negligence cause of action. It consists of two main parts:

• Cause in fact
• Proximate cause

To successfully claim negligence, the plaintiff must demonstrate that their injury was directly caused by the defendant's negligent actions.

Cause in Fact

While causation might seem obvious in many real-life scenarios, legal settings often involve intricate cases.

Tests for Cause in Fact:

• But for test
• Substantial factor test
• Unascertainable or alternative cause approach

The But For Test

The "but for" test establishes causation by determining whether the injury would not have occurred if not for the defendant's actions.

• Example: Priya swerves to avoid Danny, who is driving on the wrong side of the road, and hits a pedestrian. But for Danny's negligence, the pedestrian would not have been hit.

• The causal connection can be quite indirect, akin to the butterfly effect, but still establish "but for" causation.

  • Example: Crowd forms around the injured pedestrian, forcing a woman to walk through an alley where she is robbed. Danny's negligence is a "but for" cause of the robbery.

• Exception: If a negligent act is entirely unrelated to an injury, it cannot be considered a "but for" cause.

  • Example: A fire breaks out in an apartment building due to a tenant's negligence. A second tenant suffers burns due to a poorly maintained fire escape. The landlord's negligence in maintaining the fire escape is a "but for" cause of the burn injuries, but not of a third tenant who suffered smoke inhalation; as such the fire escape had no impact.

The Substantial Factor Test

This test is applied when multiple causes merge to result in a single injury.

• Example: Two tenants, Blaise and Amber, start separate fires that merge and injure other tenants. Neither fire is a "but for" cause on its own, since even without one fire, the other would have caused the same injuries. In such cases, if each fire was a substantial factor in causing the injury, both Blaise and Amber can be held liable.

• It also applies when multiple factors contribute to the same injury.

  • Continuing from the previous example: The negligently maintained fire escape was also a substantial factor in the burned tenant's injuries. As such, the landlord, can also be held liable, because their negligence was a substantial factor.

Unascertainable Causes or Alternative Cause Approach

This approach addresses situations where it's impossible to determine which of several negligent acts caused the injury.

• Classic Example: Summers v. Tice, where two hunters negligently fired shotguns in the direction of the plaintiff, and it was impossible to determine which hunter's bullet caused the injury. The court shifted the burden of proof to the defendants (hunters). Each defendant had to prove that their gun did not fire the shot.

• Enterprise Liability: Some courts have extended this concept to industry groups, where multiple manufacturers produce a similar product with the same defect.

  • Example: Seven drug manufacturers make the same drug, which is later found to be carcinogenic. A plaintiff who took the drug cannot identify which manufacturer produced the specific pills they ingested. Some courts may require each manufacturer to pay a portion of the damages based on their market share. This theory is not universally adopted.