Judicial notice involves a situation where a fact is either so well known or so readily verifiable that formal proof of the fact is unnecessary. A judicially noticed fact must be one not subject to reasonable dispute in that it is either (1) generally known within the territorial jurisdiction of the trial court or (2) capable of accurate and ready determination by resort to sources whose accuracy cannot reasonably be questioned.
State statutes, which vary by state, and the Federal Rules of Evidence provide the rules setting forth when the court is allowed to use judicial notice, allowing the court to take such notice, eliminating any need to prove such facts and to instruct the jury on how to consider the judicially noticed facts. In civil cases, the jury must accept as conclusive any fact judicially noticed. In criminal cases, the jury may, but is not required to accept as conclusive any fact judicially noticed.