What Is Res Ipsa Loquitur?

The law is a complex profession that requires some use of legalese. Since many legal terms are Latin, it can be difficult to understand their meaning. On the other hand, these phrases often refer to precedent and evidentiary standards in legal cases, so a basic understanding is essential.

A common phrase you might hear throughout the course of a personal injury case is “res ipsa loquitur.” In Latin, this phrase means “the thing speaks for itself.” In a personal injury case, the idea of res ipsa loquitur means that the court can assume a defendant committed negligence based on the nature of the plaintiff’s injury.

In a typical personal injury case, the claimant must show that a defendant owed the plaintiff a duty of care, that he or she breached that duty, and that his or her negligence directly led to a plaintiff’s injuries. Under res ipsa loquitur, however, a plaintiff can skip over parts one and two of the process, since the court assumes that a duty of care exists, and the defendant breached it, or committed negligence.

The Origins of Res Ipsa Loquitur

The origins of this legal doctrine date to 1863, when the court applied it to an English tort law case, Byrne v. Boadle. In this case, a barrel of flour fell from a second story loft and hit the claimant in the head. Two witnesses observed the injury, but no one saw how the barrel fell off the loft and hit the plaintiff. The court ruled that the plaintiff did not have to show direct evidence that the defendant (who was responsible for the barrel) breached his duty of care.

While this was the first formal invocation of res ipsa loquitur, the concept dates back much further, almost 2,000 years earlier, in fact.  Cicero, a Roman lawyer and politician, first invoked the term in his speech defending a friend accused of murder.

When Does Res Ipsa Loquitur Apply?

Unfortunately, your attorney cannot invoke res ipsa loquitur in every personal injury case – only in certain circumstances. Here is an example in which the doctrine might apply:

• Adam sustains an injury on an escalator and loses a leg.
• Eve’s corporation built and is responsible for maintaining the escalator.
• Adam sues Eve. Eve moves for dismissal since he never showed or offered any evidence about why the escalator malfunctioned. In other words, she argued, there is no evidence her corporation is at fault.
• The court rules that Adam does not have to prove anything other than the injury on the escalator itself, which others witnessed. The escalator evidently malfunctioned, and Eve’s corporation is responsible the escalator in every respect.
• Therefore, “the thing speaks for itself” – Adam does not have to provide more evidence to establish the first two aspects of a personal injury case.

Res ipsa loquitur is also common in medical malpractice cases. In Ybarra v. Spangard, a patient suffered complications following back surgery, but it was unclear which member of the surgical team was responsible for the injury. The court ruled that everyone breached a duty under res ipsa loquitur, as it was evident that at least one party’s negligence led to the injury.

A plaintiff may also invoke the doctrine following a surgery and subsequent discovery of a foreign object. Though the patient cannot provide specific evidence as to how the foreign object entered his or her body while he or she was unconscious, the court can infer that it should not be there. “The thing speaks for itself” – the patient does not need to prove that the physician owed the patient a duty of care or that the provider breached it. He or she must only show how that negligence led to the injury.

Res ipsa loquitur is an important legal concept that applies to certain personal injury cases. Even if you don’t know how an injury occurred, you may have a case under this doctrine.