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 Pennsylvania, judicial notice is a principle that allows courts to accept certain facts that are commonly known within the community or can be verified from unquestionable sources without requiring formal proof. This doctrine is codified in the Pennsylvania Rules of Evidence, specifically Rule 201, which outlines the types of facts that may be judicially noticed and the circumstances under which a court may do so. These include facts that are generally known within the trial court's territorial jurisdiction or can be accurately and readily determined from sources whose accuracy cannot reasonably be questioned. Pennsylvania courts can take judicial notice of both adjudicative facts—those related to the immediate case—and legislative facts that are more general and pertain to legal reasoning and the determination of law. Additionally, under Rule 202, Pennsylvania courts may take judicial notice of state, federal, and foreign laws, as well as certain municipal ordinances and regulations. The doctrine of judicial notice in Pennsylvania is designed to streamline legal proceedings by avoiding the need to prove facts that are already beyond dispute, thereby saving time and resources.