What Is Res Ipsa Loquitur?

Res ipsa loquitur is Latin for “the thing speaks for itself.” In tort law, res ipsa loquitur (just res ipsa for short) is a doctrine that means one can presume the negligence of the defendant in certain circumstances, if there is supporting evidence. Using res ipsa, a plaintiff can establish a rebuttable presumption of negligence through circumstantial evidence. In such a case, it would then be up to the defendant to prove he or she was not negligent, rather than the plaintiff bearing the burden to prove negligence. Res ipsa can be a big help to plaintiffs during personal injury cases, but it’s often difficult to assert.

Defining Res Ipsa Grounds of Liability

The evidentiary rule of res ipsa loquitur will only come into play if the plaintiff has circumstantial evidence that makes the defendant’s negligence obvious – or that makes it speak for itself. Circumstantial evidence can be anything that points to negligence as the logical conclusion or inference under the circumstances.

In the very case that first used the res ipsa doctrine in a court of law (Byrne v. Boadle), the plaintiff was suing because of a barrel of flour that fell from the second story and struck him. There were no witnesses, and the plaintiff could provide no evidence of the defendant’s negligence. Yet the accident itself provided enough circumstantial evidence that the court ruled in favor of the plaintiff. This first case of res ipsa changed the common tort laws and made it possible for plaintiffs to sometimes place the burden of proof on the defendant.

What Would Qualify for a Res Ipsa Loquitur Assertion?

Most personal injury cases come with a significant burden of proof on the injured party. It is the plaintiff’s job to prove that the defendant breached a duty, and that this act of negligence or recklessness caused the accident and injuries. In the event that direct evidence of the defendant’s breach of duty does not exist, the plaintiff can instead try to assert res ipsa loquitur. For a plaintiff to successfully assert res ipsa, he or she would need three elements:

  1. The incident would likely not have had happened were it not for negligence. The incident must be of the type wherein a reasonable person could infer that negligence must have played a role.
  2. The thing that caused the incident was in the defendant’s control. To accurately name a defendant without clear evidence, the plaintiff must have proof the product, animal, property hazard, or other source of injury was solely in the defendant’s control.
  3. The plaintiff did not contribute to his or her own injuries. Finally, the plaintiff must show he or she did not cause the harmful thing to occur. This can be an especially difficult element to prove when there were no witnesses, as well as in cases where plaintiff contributory negligence is a common defense, such as in slip and fall lawsuits.

In many claims today, the doctrine of res ipsa seems to have fallen mostly out of use. Not many petitions attempt to assert res ipsa anymore, and those that do try encounter increasing resistance to allow a res ipsa basis for liability go to jury trial. This may be because modern legislation restricts the grounds on which a plaintiff can secure recovery. Restrictions are especially abundant in the medical malpractice field, where most states have enacted damage caps, affidavits of merit, and many other rules and requirements restricting who can recover damages. Today, it’s more difficult than ever for plaintiffs to prove res ipsa liability, but an attorney can certainly improve the odds.