Res Ipsa Loquitur: Legal Elements & Definition Guide


Let’s say you sustained an injury due to someone else’s negligence. You know undoubtedly it was that particular person who caused the incident. But, there is one major problem – you don’t have any evidence to prove that person was negligent. The legal doctrine of res ipsa loquitur, res ipsa for short, allows a judge or jury to presume negligence on the part of the defendant without proving it.  This article will further explain the res ipsa loquitur meaning, defenses of res ipsa, and how negligence plays a role in this legal doctrine. 

Understanding Negligence

To get a better grasp of the res ipsa meaning, you first need to understand the concept of negligence. For a personal injury case to be successful, the victim (i.e. plaintiff) needs to establish negligence on the person who allegedly injured them (i.e. defendant). To establish negligence, the plaintiff must prove the following:

  • Duty: Defendant had a duty to care for the victim.
  • Breach of duty: Defendant failed to provide this care.
  • Causation: The breach of duty caused the victim’s injuries.
  • Damages: The victim was indeed injured.

The plaintiff has the burden of proof to demonstrate these four elements of negligence.

What is Res Ipsa Loquitur

The res ipsa loquitur definition asserts that negligence can be presumed without proof. This is because there could be no other alternative explanation but negligence on the part of the defendant. In other words, while there is no direct proof of negligence, the injuries sustained by the victim cannot be explained by anything else except for negligence.  Res ipsa loquitur, which translates to “the thing speaks for itself,” utilizes circumstantial evidence to build a case by inference. This means you can prove a fact to be true through reasonable inference of certain events or happenings relevant to the injury.  The burden of proof shifts from the plaintiff, who was required to prove negligence, to the defendant, who now requires to prove they were not negligent. Example: Eliora is walking past a 2-story commercial building. At the time, construction and renovations are being done to this building by a construction company, Alliance Construction Co. As Eliora walks by the building, a wrench falls onto her head. She sustains traumatic brain injury as a result. Eliora and her legal team can’t prove negligence on the part of Alliance Construction Co. since no one saw any worker dropping the wrench. However, the jury awards her full compensation on the basis of res ipsa loquitur. Even though there was no direct evidence, the event of a wrench dropping by the building cannot be explained by anything but negligence on the part of Alliance Construction Co.

Elements of Res Ipsa Loquitur

The plaintiff must demonstrate three res ipsa loquitur elements to prove the defendant’s negligence:

  1. The event could not have happened unless negligence took place.
  2. The event that occurred was exclusively in the control of the defendant.
  3. The plaintiff could not have caused the incident.

Let’s apply these three elements to our previous example:

  • Element 1: A wrench dropping from the building does not ordinarily happen without some sort of negligence.
  • Element 2: The wrench obviously belonged to Alliance Construction Co., the construction company working on-site at the time.
  • Element 3: Eliora was merely a pedestrian walking by at the time – not in any way connected to the wrench falling.

By establishing these three elements, the plaintiff can successfully bring a case of res ipsa against the defendant.

Defenses to Res Ipsa Loquitur

If the plaintiff is successful in demonstrating all three elements of res ipsa, the defendant has the opportunity for rebuttal. They can challenge any one of the three elements of your res ipsa case. For instance, the defendant could make a case that the victim contributed to the incident in some way. Revisiting our previous example, if Eliora walked through an area marked-off by warning tape, the construction company could argue that she should not have been there in the first place. By walking through a marked-off area, she contributed to the incident knowing very well it was a hazardous area. As discussed, a successful negligence case requires the plaintiff to prove four elements: duty, breach of duty, causation, and damages. A res ipsa loquitur case covers the first three, namely, duty, breach of duty, and causation.  In order to file a successful personal injury suit, the plaintiff still needs to prove harm. This can be done through medical bills or doctor’s reports.  

Valiente Mott

If you were involved in an accident but not sure if you have enough evidence required for a successful case, consult with our team of legal experts at Valiente Mott. Our personal injury attorneys experts will assess your situation and let you know whether you have grounds for a negligence or even a res ipsa loquitur case. Contact us today at (702) 623-2323 for your free consultation! 

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