burden of proof

American  

noun

1. Chiefly Law. the obligation to offer evidence that the court or jury could reasonably believe, in support of a contention, failing which the case will be lost.

2. the obligation to establish a contention as fact by evoking evidence of its probable truth.

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burden of proof British  

noun

1. law the obligation, in criminal cases resting initially on the prosecution, to provide evidence that will convince the court or jury of the truth of one's contention

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burden of proof Idioms  

1. Obligation of proving a disputed charge or allegation. For example, Are you sure you mailed the tax return on time? The burden of proof's on you. A legal term dating from the late 1500s, it has also been used more loosely in recent times.

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Etymology

Origin of burden of proof

First recorded in 1585–95

Example Sentences

“The stock’s dip is probably more panic and less thesis collapse. Until proven otherwise, Nvidia is still the leader, but the burden of proof has shifted,” said Bill Birmingham, managing director of REX Financial.

From Barron's • Apr. 1, 2026

All that said, here’s the harsh truth: It’s extremely difficult to contest a will, and the burden of proof lies with your friend’s sister.

From MarketWatch • Jan. 7, 2026

Apparently, Kennedy has never heard of the burden of proof or the extreme difficulty in proving a negative.

From Salon • Nov. 29, 2025

However, he explained that the burden of proof in criminal cases lay with the prosecution – they had to prove who fired the shots.

From BBC • Oct. 23, 2025

Hence, it is the presumption of common sense and science that these ESP phenomena don’t exist, and the burden of proof is on those who maintain that there are such phenomena.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos

Related Words

• onus