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What Is Res Ipsa Loquitur?

By Butler Prather LLP on April 27, 2020

Most personal injury cases revolve around the negligence of one person causing harm to another. Victims in a personal injury lawsuit have a burden of proving they were hurt because of the actions of another person. In most cases, the victim will have to produce evidence to substantiate their claims.

However, what if there is no direct evidence to show that another person was negligent, but you are certain they are to blame? This is where the legal doctrine of res ipsa loquitur could be helpful.

What Is Res Ipsa Loquitur?

Breaking down “res ipsa loquitur”

The phrase “res ipsa loquitur” is Latin and means that “the thing speaks for itself.” On its own, that will likely make no sense. However, in personal injury law, res ipsa loquitur acts as an evidentiary rule that allows a victim (plaintiff) in a personal injury case to establish a presumption of negligence on the part of the at-fault party (the defendant) through the use of circumstantial evidence.

By using res ipsa loquitur, a plaintiff will need to prove the defendant’s negligent state of mind through various circumstantial facts, and the defendant will have the burden of proving that they were not negligent.

Res ipsa loquitur and evidence law

Accidents that cause injuries happen all the time, but that does not necessarily mean that another person’s negligence caused the accident. In most cases, there needs to be evidence to show that a defendant is negligent and that the negligence resulted in a plaintiff’s injury. When direct evidence does not exist, “circumstantial evidence” can be used to establish negligence.

Circumstantial evidence consists of facts that point to a logical conclusion of negligence, but does not demonstrate negligence outright. This type of evidence allows judges and juries to infer negligence based on the totality of facts and circumstances, along with shared knowledge that arises out of shared human experiences.

Elements of res ipsa loquitur

There is a basic formula that most states use to determine the elements of res ipsa loquitur. In general, there are three requirements that a plaintiff (or their attorney) must meet before a jury is allowed to infer the defendant was negligent:

  • The incident in question does not normally occur unless someone has acted negligently.
  • The evidence presented has ruled out the possibility that the plaintiff caused their injury or that a third party caused the injury.
  • The negligence in question falls within the scope of duty that the defendant owed to the plaintiff at the time the incident occurred.

An example of how res ipsa loquitur could work

Suppose for a moment you are walking down the street next to a brewery, when suddenly a giant barrel of yeast falls out of a window. The barrel strikes you, and you sustain severe head and spinal cord trauma. There was a witness who saw the barrel fall out of the window, but they did not see what caused it to fall.

You decide to file a lawsuit against the brewery, alleging that the owner is liable for the injuries you sustained. In this incident, there is no direct evidence that the owner caused the injury or that their negligence caused the barrel of the yeast to fly out the window. However, there is no other explanation of how the barrel left the window of the brewery and crashed onto you.

This scenario meets the three elements of res ipsa loquitur mentioned above: it is not an incident that normally occurs unless someone has acted negligently, the evidence ruled out the possibility that you caused the injury or that a third party caused the injury, and the brewery owner had a duty to ensure that barrels do not fall out of the window and cause harm to others.

Posted in: Personal Injury


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