Also known as:onus probandi's · onus · burden of proof
Written by attorneys — see sources below.
A party's duty to prove a disputed assertion or charge. It encompasses both the burden of production and the burden of persuasion.
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How its tested
Common Examples
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Alternative Liability in Negligence
Oakley Osei was injured when one of two negligent drivers struck her car but could not identify which one. Both defendants had acted tortiously toward her. Each defendant therefore had to prove his own conduct did not cause the harm. When neither could do so, both remained liable for the full injury.
Will Contest Burden Allocation
Orion Orlov petitioned to probate a will and offered prima facie proof of due execution. Octavia Okonkwo contested the will and alleged undue influence. The proponent therefore carried the initial burden on execution while the contestant carried the burden on the claim of undue influence.
Omar Olson suffered a single indivisible injury from the combined negligence of two construction firms. One firm sought to limit its liability by showing the harm could be apportioned. That firm therefore bore the burden of proving the proper division of damages.
Gender Classification Scrutiny
Opal Okoro challenged a state university policy that treated male and female applicants differently for athletic scholarships. The state therefore had to supply an exceedingly persuasive justification showing the classification served an important objective and was substantially related to it.
Plaintiff's Causation Burden
Orla O'Malley sued a single manufacturer alleging its product caused her illness. Because only one actor's conduct was at issue, she carried the burden of proving that the defendant's tortious conduct caused her harm.
Equitable Relief in Corporate Dispute
Olympus Banking sued a former director for allegedly usurping a corporate opportunity. The director had not followed the statutory safe-harbor procedures before pursuing the opportunity. The plaintiff therefore retained the burden of proving that the director breached a duty to the corporation.
Guaranty Trust Co. v. York[326 U.S.] at 110
In May 1930 the Van Sweringen Corporation issued $30,000,000 in notes under an indenture naming Guaranty Trust Co. of New York as trustee with power to enforce noteholders' rights. In October 1930 Guaranty and other banks advanced large sums to companies affiliated with the Corporation and controlled by the Van Sweringens. When the Corporation could not meet its obligations, Guaranty participated in an exchange plan under which noteholders could surrender their notes for cash equal to 50 percent of face value plus twenty shares of Van Sweringen stock per $1,000 note; the offer remained open until December 15, 1931.
In 1934 respondent York received $6,000 of the notes as a gift from a donor who had not accepted the exchange offer. In April 1940 three accepting noteholders filed the Hackner suit in federal court charging Guaranty with fraud and misrepresentation in connection with the exchange. York's motion to intervene was denied, and summary judgment for Guaranty was affirmed on appeal.
On January 22, 1942, after her exclusion from the Hackner litigation, York filed the present class action in the United States District Court for the Southern District of New York on behalf of non-accepting noteholders. The complaint, resting exclusively on diversity of citizenship, alleged that Guaranty had breached its trust by failing to protect noteholders' interests when it assented to the exchange offer and by failing to disclose its own self-interest.
The district court granted Guaranty's motion for summary judgment on the authority of the Hackner decision. The Circuit Court of Appeals reversed, holding that a federal court sitting in equity is not required to apply the New York statute of limitations that would govern an identical suit in the New York state courts. The Supreme Court granted certiorari.
It includes both the burden of production and the burden of persuasion. The party with the burden must introduce evidence on an issue and ultimately convince the factfinder on that issue.
How does onus probandi differ from burden of production?
The burden of production requires a party to come forward with some evidence on an issue. The burden of persuasion requires that party to convince the factfinder that the assertion is true.
When does the burden of proof shift to the defendant in tort cases?
It shifts when multiple negligent defendants each could have caused the plaintiff's harm but the plaintiff cannot identify which one did. Each defendant must then prove its conduct was not the cause in fact of the injury.
Who bears the burden in a will contest under the Uniform Probate Code?
The proponent must establish due execution. The contestant must establish lack of capacity, undue influence, fraud, or revocation.
What burden applies when multiple tortfeasors seek to apportion damages?
Each actor seeking to limit liability by showing the harm is apportionable must prove the proper division among the actors.
410 U.S. 113 (1973)
…or overbroad." A physician's abortion conviction was affirmed. In Thompson , n. 2, the court observed that any issue as to the burden of proof under the exemption of Art. 1196 "is not before us." But see Veevers v. State , 172 Tex. Cr. R. 162, 168-169, 354 S. W. 2d 161, 166-167 (1962). Cf. United States v. Vuitch , 402 U. S.…