Liability

What is Res Ipsa Loquitur?

A doctrine that infers negligence from the nature of an accident in cases where direct evidence of negligence is unavailable.

Definition

Latin for 'the thing speaks for itself.' Res ipsa loquitur allows a jury to infer negligence when (1) the accident is of a type that ordinarily doesn't happen without negligence, (2) the instrumentality was under the defendant's exclusive control, and (3) the plaintiff didn't contribute to the harm.

How it applies in personal injury cases

Most common in medical malpractice (retained foreign objects, wrong-site surgery), product liability, and elevator/escalator cases. When applicable, it shifts the burden of explanation to the defendant — a powerful procedural advantage at trial.

Related terms

Negligence Per Se

A doctrine where violating a safety statute is automatically considered negligence, eliminating the need to prove duty and breach separately.

Standard of Care

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

Causation

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

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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