Rule 450 Judicial notice may not be taken of any matter unless authorized or required by law.

Judges cannot simply decide on their own that something is a known fact during a trial. There has to be a specific law that allows or requires the judge to treat that fact as automatically true.

This protects people in court by making sure judges follow clear rules about what counts as common knowledge. Without this rule, a judge could assume things that might actually need to be proven with evidence.