Onus Probandi
Literal meaning: “Burden of proving”
What does the Latin term "Onus Probandi" mean in law?
Onus probandi refers to the obligation placed on a party in legal proceedings to prove or disprove a disputed fact or assertion. In civil cases, the onus probandi typically rests on the plaintiff, who must establish each element of the claim by a preponderance of the evidence. In criminal cases, the prosecution bears the onus probandi and must prove guilt beyond a reasonable doubt. The burden may shift during trial; for instance, once the plaintiff establishes a prima facie case, the burden of production may shift to the defendant to come forward with rebutting evidence. The allocation of the onus probandi profoundly affects litigation outcomes because the party bearing the burden loses if the evidence is in equipoise.
Source: Evidence · Legal Latin
Legal Definition
Onus probandi refers to the obligation placed on a party in legal proceedings to prove or disprove a disputed fact or assertion. In civil cases, the onus probandi typically rests on the plaintiff, who must establish each element of the claim by a preponderance of the evidence. In criminal cases, the prosecution bears the onus probandi and must prove guilt beyond a reasonable doubt. The burden may shift during trial; for instance, once the plaintiff establishes a prima facie case, the burden of production may shift to the defendant to come forward with rebutting evidence. The allocation of the onus probandi profoundly affects litigation outcomes because the party bearing the burden loses if the evidence is in equipoise.
How It's Used
Judges issue instructions on the onus probandi to ensure jurors understand which party must prove which facts and to what standard. Motions for summary judgment and directed verdict turn on whether the party bearing the onus probandi has produced sufficient evidence to create a genuine issue for trial.
Example Sentences
In a medical malpractice case, the onus probandi falls on the plaintiff to prove that the physician's care fell below the accepted standard and caused the injury.
The court shifted the onus probandi to the employer after the plaintiff established a prima facie case of discriminatory termination.
Because the prosecution failed to meet its onus probandi of proving guilt beyond a reasonable doubt, the jury returned a verdict of not guilty.