Evidence in court must be admissible. The rules of admissibility are complex. Certain facts are admissible pursuant to the doctrine of “judicial notice.” “It cannot certainly be laid down as a universal, or even as a general proposition, that the court can judicially notice matters of fact. Yet it cannot be doubted, that there are many facts, particularly with respect to geographical positions, of such public notoriety, and the knowledge of which is to be derived from other sources than parol proof; which the court may judicially notice.” Peyroux v. Howard, 32 U.S. 324, 342 (1833).
The particular state’s evidence code should be relied upon when a party requests that a court take judicial notice of common facts, including the most obvious of facts, maps, historic events, etc. A court might be unable to take judicial notice unless the subject is specified by statute. See, i.e., California Evidence Code section 450450: “Judicial notice may not be taken of any matter unless authorized or required by law.”