Courts recognize that a bad result or unsuccessful result of medical care and treatment does not, by itself, prove that the physician committed medical malpractice. “The law will not hold a physician liable for every bad result; some evidence of a violation of an objective standard of care must be shown.”¹

There is an exception to the rule that bars a presumption of malpractice arising merely from an unsatisfactory medical procedure. That exception goes by the Latin name, “Res Ipsa Loquitur.” As explained by a California court: “… the maxim res ipsa loquitur translated means simply ‘the thing, or affair, speaks for itself,’ and, so speaking, authorizes the inference of negligence in the absence of a showing to the contrary.”²

Res Ipsa Loquitur is a legal principal that is applied in courts around the country. In some states, Res Ipsa Loquitur is enshrined in statutes. In other states, the doctrine has been developed by judges through caselaw.

Plaintiffs’ counsel sometimes try to persuade the judge that plaintiffs are entitled to enjoy at trial an inference of negligence. Such a “Res Ipsa Inference” allows attorneys for plaintiffs to argue to juries that the jurors may infer, not must infer, negligence from the fact that the defendant-physicians were negligent because the medical outcome would not have occurred if the physicians had met the standard of care.

Defense counsel may offer expert testimony in response to show that, even with due care on the part of the physician, the patient’s injury still could have occurred. A jury is not required to accept plaintiff’s proposed Res Ipsa Inference. The jury may reject that inference if the jury finds that the medical facts and medical testimony (such as testimony from the defendant physician, a treating physician, or a medical expert) demonstrate that the unfortunate medical result, alone, does not show negligence.

I. Elements for Proving Res Ipsa Loquitur

Under the doctrine of Res Ipsa Loquitur, “a fact-finder may infer negligence merely from the happening of the event that caused the harm if: (1) the event is of a type that ordinarily would not occur in the absence of negligence; (2) it is caused by an agency or instrumentality under the exclusive control of the party charged with negligence; and (3) it is not due to any voluntary action or contribution on the part of injured party.”³ If plaintiff does not establish all 3 elements, then plaintiff will not be allowed to rely upon a Res Ipsa Inference.

II. The Medical Outcome Would Not Have Occurred Absent Negligence

The fact that a bad outcome resulted from medical care is not sufficient for plaintiff to rely upon Res Ipsa Loquitur. Instead, plaintiff must show that, based upon the nature and factual circumstance surrounding the bad outcome, the injury would not have occurred unless the physician was negligent. The rule of Res Ipsa Loquitur “simply recognizes what we know from our everyday experience: that some accidents by their very nature would ordinarily not happen without negligence…”⁴

III. Foreign Objects Inadvertently Left in a Patient’s Body

A classic example of a situation where the Res Ipsa Inference may apply is where a foreign object, such as a scalpel blade or a sponge, is left in the patient’s body after the patient is closed at the end of a surgical procedure.

“The very fact that [surgeon] reopened the incisions in his attempts to retrieve the missing [foreign object] once he discovered that [the object] had not been accounted for shows that there was no good purpose for leaving the” foreign object in the patient, explained a judge in a case in which a scalpel blade detached from its handle and lodged in the patient’s knee joint because defendant surgeon inadvertently left the blade in the patient’s knee when he closed the surgical incisions.⁵

IV. Injuries Remote From an Operative Site

An unexplained injury may arise in an area of the patient’s body remote from the area that was being treated by a physician. In that case, a Res Ipsa Inference may be warranted.

A court found that Res Ipsa Loquitur applied in a case in which there was “no problem of negligence in treatment, but of distinct injury to a healthy part of the body not the subject of treatment, nor within the area covered by the operation… [S]uch circumstances raise the inference of negligence and call upon the defendant to explain the unusual result.” In that case, the patient had undergone appendectomy for appendicitis. After the operation, the patient felt a sharp pain about halfway between his neck and his right shoulder. The court held that Res Ipsa Loquitur applied.⁶ Another classic example would be a burn to a portion of the patient’s body distant from the surgery itself.

V. Exclusive Control Over the Agent of Harm

Even if it is unknown precisely how a patient suffered harm, all of the medical providers who were involved in the medical procedure at issue may face a Res Ipsa Inference—unless each provider can show to a reasonable degree of medical certainty that he or she did not have any control of the procedure. A court may conclude that, “[a]lthough it is unknown how th[e] injury occurred, [the surgeon and physicians’ assistants] and those in the operating room were in control of any instrumentality that could have caused it, and each owed a common duty to” plaintiff.⁷

VI. The Patient’s Own Comparative Negligence

Res Ipsa Loquitur applies only if the medical event that caused the patient’s injury was not caused or contributed to by any negligence on the part of the patient. A patient who is unconscious or anesthetized at the time of the medical care at issue will not be considered to be negligent or a contributing cause of his or her injury arising from that care during unconsciousness. In cases involving injuries arising during surgery, the evidence may “show[ ] that [plaintiff] did not play a voluntary role in the damage… because she was unconscious during her” surgery.⁸