Probative

Relevance, in the common law of evidence, is the tendency of a given item of evidence to prove or disprove one of the legal elements of the case, or to have probative value to make one of the elements of the case likelier or not. Probative is a term used in law to signify "tending to prove." Probative evidence "seeks the truth". Generally in law, evidence that is not probative (doesn't tend to prove the proposition for which it is proffered) is inadmissible and the rules of evidence permit it to be excluded from a proceeding or stricken from the record "if objected to by opposing counsel." A balancing test may come into the picture if the value of the evidence needs to be weighed versus its prejudicial nature.

Until the Federal Rules of Evidence were restyled in 2011, Rule 401 defined relevance as follows:

"Relevant evidence" means evidence having any tendency to make the existence of any fact that is of consequence to the determination of the action more probable or less probable than it would be without the evidence.

This definition incorporates the requirement that evidence be both material ("of consequence to the determination of the action") and have probative value ("having any tendency to make the existence of any [material] fact...more probable or less probable than it would be without the evidence"). The restyled Rule 401, however, separates these traditional concepts in order to make the rule clearer and more easily understood. The amended language essentially rewrites the rule as a test, rather than a definition, for relevance:

Evidence is relevant if:

According to the notes of the Advisory Committee appointed to draft the Federal Rules of Evidence,

Relevancy is not an inherent characteristic of any item of evidence but exists only as a relation between an item of evidence and a matter properly provable in the case.

The United States Court of Appeals for the District of Columbia Circuit explains the concept of "matter properly provable" as follows:

The initial step in determining relevancy is therefore to identify the "matter properly provable." As Professor James explained in a highly-regarded article, '[t]o discover the relevancy of an offered item of evidence one must first discover to what proposition it is supposed to be relevant."

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Wikipedia