Judicial notice

Judicial notice is a rule in the law of evidence that allows a fact to be introduced into evidence if the truth of that fact is so notorious or well known, or so authoritatively attested, that it cannot reasonably be doubted. This is done upon the request of the party seeking to rely on the fact at issue. Facts and materials admitted under judicial notice are accepted without being formally introduced by a witness or other rule of evidence, and they are even admitted if one party wishes to lead evidence to the contrary.

Judicial notice is frequently used for the simplest, most obvious common sense facts, such as which day of the week corresponded to a particular calendar date or the approximate time at sunset. However, it could even be used within one state to notice a law of another state—such as one which provides average baselines for motor vehicle stopping distances.

In the United States, Article II of the Federal Rules of Evidence ("FRE") addresses judicial notice in federal courts, and this article is widely copied by U.S. States. FRE 201(b) permit judges to take judicial notice of two categories of facts:

The FRE also notes that judicial notice may be permissive or mandatory. If it is permissive, then the court may choose to take judicial notice of the fact proffered, or may reject the request and require the party to introduce evidence in support of the point. If it is mandatory, then the court must take judicial notice of the fact proffered. Although the FRE does not expand upon the kinds of facts that would fall into one category or another, courts have ruled that judicial notice must be taken of federal public laws and treaties, state public laws, and official regulations of both federal and local government agencies.

FRE 201(f) establishes that the effect of the court taking judicial notice is different in civil and criminal trials. In a civil trial, the fact taken notice of is thereby conclusively proved. In a criminal case, the defendant has the right to contest every fact that might tend to incriminate him. Therefore, the court taking judicial notice would simply allow the jury to make the finding that the court took notice of, but would not require this outcome, and would not prevent the defense from presenting evidence to rebut the noticed fact.

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Wikipedia