The Law of Falling Objects: Byrne V. Boadle and the Birth of Res Ipsa Loquitur.

INTRODUCTION In Latin, the phrase res ipsa loquitur means "the thing speaks for itself." In the law, few concepts have created more confusion among scholars and practitioners than the evidentiary doctrine of res ipsa loquitur. Commentators have attempted to characterize the phrase alternatively as a rule, principle, doctrine, maxim, and for one particularly frustrated scholar, a myth. (1) Likewise, res ipsa loquitur has resisted all attempts by legal authorities to delineate its scope. In the words of another eminent, but exasperated, scholar, res ipsa loquitur "is used in different senses[;] ... it means inference, it means presumption, it means no one thing--in short it means nothing." (2) Nonetheless, the maxim has appeared in thousands of cases since its first articulation in the mid-nineteenth century and shows no signs of leaving the legal lexicon. The most widely accepted interpretations of res ipsa loquitur include (3): (1) that it creates a permissible inference of negligence for a jury in situations where a plaintiff can only show that an injurious event occurred; (2) that it presents a rebuttable presumption requiring a jury to find for a plaintiff in the absence of exculpatory evidence from the defendant; or (3) that it forces an affirmative shift in the burden of proof from plaintiff to defendant. (4)