Liability

What is Causation?

The legal requirement that a defendant's negligence directly caused the plaintiff's injury.

Definition

Causation has two components: actual cause (the 'but-for' test — but for the defendant's conduct, would the harm have occurred?) and proximate cause (was the harm a foreseeable consequence?). Both must be proven for liability to attach.

How it applies in personal injury cases

Causation is the most common case-killer in medical malpractice. Even with a clear standard-of-care breach, if the patient would have suffered the same outcome anyway (e.g., the cancer was already terminal), the case fails on causation. Pre-existing conditions and alternative causes need to be screened for at intake.

Related terms

Standard of Care

The level of care a reasonably prudent person (or professional) would exercise under similar circumstances.

Discovery Rule

A rule that postpones the start of the SOL clock until the plaintiff discovers (or reasonably should have discovered) the injury.

Premises Liability

Liability of property owners and occupiers for injuries that occur on their premises due to dangerous conditions.

This entry is a plain-English reference for personal injury practice. It is not legal advice — consult a licensed attorney in your jurisdiction for the law applicable to your case.

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