Proximate Cause in Negligence Cases

Proximate Cause

Proximate cause is a limitation on factual cause in negligence cases.
It requires that the harm resulting from the defendant's negligent act was foreseeable.

Direct cause involves a direct chain of events from the defendant's negligence to the plaintiff's injury, without intervening forces.

Danny negligently drives on the wrong side of the street, causing Priya to swerve.
Priya's car hits a toolbox, and a screwdriver pierces Penny's thigh.
It is foreseeable that someone on the sidewalk could be injured by Danny's driving, so Danny is liable.

If the defendant's negligence creates a risk of harm, but an entirely different and unforeseeable type of harm results, the negligence is not the proximate cause.

Danny's negligent driving causes Priya to swerve. Penny alters her path to avoid being hit and falls through a deteriorating sidewalk grate into an electrical transformer vault.
Danny is not liable because falling through a grate is not a foreseeable consequence of negligent driving.

Indirect cause involves an independent intervening force that comes into motion after the defendant's negligent act and combines with it to cause injury.
Proximate cause here is limited by foreseeability.

The question is whether the defendant's negligence increased the risk that the independent force would harm the plaintiff.

Penny is robbed in an alley she walks down due to Danny's negligent driving.
It's a stretch to say negligent driving increases the risk of robbery, so Danny is not liable.

Criminal acts are not always unforeseeable. If negligence makes it more likely that the intervening act will occur, liability is not cut off.
- Example: Negligently leaving keys in a car's ignition makes it more likely a thief will steal the car.
Intervening acts of God: If the defendant's negligent act made it more likely that the act of God would cause injury, the negligent act will be the proximate cause of the injury.
- Example: Danny's negligent driving causes Priya to swerve and hit a toolbox, sending a screwdriver onto an awning. A strong wind blows the screwdriver off, injuring Penny. Danny is liable.
If Penny is struck by lightning while walking in the alley, Danny's negligent driving was not a proximate cause of Penny's injury.

If both the result and the intervening force are foreseeable, the defendant's act will be the proximate cause.

A tortfeasor is liable for subsequent simple malpractice related to the injury they caused.
- Example: Penny's eye is grazed by a screwdriver, and a doctor's malpractice makes it worse. Danny is liable for the aggravation.

An original tortfeasor is liable for later injuries resulting from botched rescues.
- Example: A passerby drops Penny while trying to rescue her from a collapsing grate. Danny is liable.

An original tortfeasor also is liable for later injuries resulting from the original injury weakening the victim.
- Example: Penny breaks her other leg while using crutches after screwdriver injury. Danny is liable.

Such intervening forces are superseding forces because they break the causal chain.

Penny parks negligently, blocking a road. Priya takes a detour and is hit by Danny's car.
Penny's negligence is not the proximate cause of Priya's injury; Danny's negligent driving is a superseding cause.

The fact that the extent or severity of the harm was not foreseeable does not relieve the defendant of liability.
A tortfeasor takes their victim as they find them (eggshell plaintiff rule).

If Danny barely taps Priya's car, but Priya has a previous back injury that is reaggravated, Danny is liable for the full extent of the injury.
If Danny causes significant damage to Priya's exotic sports car, Danny is liable for the full cost of repair, even if it's much higher than for a regular car.