The legal term “res ipsa loquitur” is a Latin phrase that literally means “the thing speaks for itself.”  The doctrine of res ipsa loquitur permits an inference of negligence “when an accident is of the kind that does not ordinarily happen unless the defendant was negligent in some respect and other responsible causes including conduct of the plaintiff are sufficiently eliminated by the evidence.”  This definition, however, is not as straightforward as it first appears because the law also recognizes that “the mere happening of an accident does not establish negligence.” As a result the doctrine is reserved for rare cases and used as a last resort.

In order for the doctrine to apply, the plaintiff must establish by a preponderance of the evidence that “(1) the instrumentality causing the accident was in the sole and exclusive control and management of the defendant; and (2) the accident is of the type or kind that would not happen in the ordinary course of things unless there was negligence by the defendant.”  In practice, the doctrine is most often seen in cases of medical negligence dealing with medical equipment or anesthetized patients. For example, in one case where the doctrine was applied, a patient received an infected kidney during a transplant procedure. In another case, a patient used the doctrine to support his claim against a hospital for unexplained burns sustained during surgery.

In a recent Massachusetts case, a patient plaintiff successfully relied on the doctrine to defeat summary judgment in his products liability claim against the manufacturer of a surgical guide wire that broke during surgery and was left inside the plaintiff’s heart. None of the parties argued that the physicians who performed the surgery were negligent in their handling or use of the guide wire, which left only the manufacturer to blame. However, through no one’s fault, the subject wire was no longer available for examination. Unable to otherwise prove that the product was defective, the plaintiff relied on the res ipsa loquitur doctrine.  In response and in its motion for summary judgment, the manufacturer argued that the physicians were using the guide wire in an ‘off-label’ manner and that its guide wires were manufactured with sufficient strength for the uses approved by the FDA, and further that the doctrine of res ipsa loquitur did not apply.

In finding for the plaintiff and allowing the case to proceed to trial, the District Court judge noted that leading surgeons in a prominent teaching hospital had used the guide wire in the same manner thousands of times and the manufacturer had provided no evidence that the use was an unforeseeable misuse of the wire. The judge further found that there was no controlling legal authority that immunized the manufacturer from a product defect claim based on a foreseeable ‘off-label’ use.  The trial court judge also determined that the plaintiff had sufficiently supported negligence under the res ipsa loquitur theory. The judge noted that there was no evidence of mishandling of the guide wire which satisfied the requirement of exclusive control. The judge relied on evidence from a reputable surgeon who testified that he had performed more than 15,000 similar procedures and had experienced guide wire breakage fewer than six times, to support the conclusion that the guide wire would not have broken absent the manufacturer’s negligence.