Judicial notice is a court’s acceptance of a well-known and indisputable fact without requiring the party relying on the fact to prove it. The doctrine of judicial notice is one of common sense, and is based on the theory that where a fact is well-known in the community—or its existence is easily determined from sources that cannot be reasonably questioned—it would not be a good use of judicial time and resources to require formal proof of the fact in court. A court may take judicial notice of both facts and laws.

In Colorado, judicial notice is governed by Colorado Rules of Evidence (CRE) 201, which aligns with the principles of the federal rules. Under CRE 201, a court may take judicial notice of a fact that is not subject to reasonable dispute because it is either generally known within the territorial jurisdiction of the court or can be accurately and readily determined from sources whose accuracy cannot reasonably be questioned. This includes both adjudicative facts and law. Adjudicative facts are those that typically relate to the parties or events in a particular case, while laws include statutes, judicial decisions, and regulations of both Colorado and other jurisdictions, as well as public records and government documents. The court may take judicial notice at any stage of the proceeding, and once a court takes judicial notice of a fact, it is accepted as conclusive in civil cases. In criminal cases, however, the jury is instructed that it may, but is not required to, accept as conclusive any judicially noticed fact.