Best evidence rule

The best evidence rule is a legal principle that holds an original copy of a document as superior evidence. The rule specifies that secondary evidence, such as a copy or facsimile, will be not admissible if an original document exists and can be obtained. The rule has its roots in 18th century, British law.

The best evidence rule has its origins in the 18th century case Omychund v Barker (1745) 1 Atk, 21, 49; 26 ER 15, 33. Wherein Lord Harwicke stated that no evidence was admissible unless it was "the best that the nature of the case will allow".

According to Blackstone's Criminal Practice the best evidence rule in England and Wales as used in earlier centuries "is now all but defunct".Lord Denning MR says that "nowadays we do not confine ourselves to the best evidence. We admit all relevant evidence. The goodness or badness of it goes only to weight and not to admissibility."

In the United States the best evidence rule is part of Article X of the Federal Rules of Evidence (Rules 1001-1008). The rule specifies the guidelines under which one of the parties of a court case may request that it be allowed to submit into evidence a copy of the contents of a document, recording or photograph at a trial when the "original document is not available." If the party is able to provide an acceptable reason for the absence of the original then "secondary evidence" or copies of the content in the original document can be admitted as evidence. The best evidence rule is only applied in situations in which a party attempts to substantiate a non-original document submitted as evidence during a trial.

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