Byrne v Boadle · English Court of Exchequer · 1863

Can he win without proof of carelessness?

Short answer: Yes: the thing speaks for itself.

The facts. A man walking down a Liverpool street was hit by a barrel of flour falling from a warehouse window above. He couldn't show what went wrong, or who dropped it. The trial judge threw out his case.

The ruling. Byrne v Boadle (1863): The court held that barrels don't fall from windows without negligence, starting the 'res ipsa loquitur' rule, meaning the thing speaks for itself.

Chief Baron Pollock coined the phrase in argument. It remains a staple for injured people who can't see how an accident happened.

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For fun, not legal advice.