Mandatory authority consists of primary sources of law and it is binding and must be followed. Some examples are constitutions, statutes, legislation, and administrative rules.
But mandatory authority is not followed in a case of first impression. A case of first impression is when the governing jurisdiction has not decided or ruled on a particular legal issue, so there is no precedent. If mandatory authority in the area does not exist, mandatory authority from other jurisdictions is used and becomes persuasive authority.
When citing persuasive authority rather than binding, it is important to explain why the court should follow that precedent. Such explanations may include:
- Although this is a case of first impression, other courts that have heard the issue have come to the same conclusion;
- The decision from the other court is based on statutory language, public policy considerations, etc. and it identical to the issue before the court;
- The decision from the other court is factually indistinguishable from the current case; and/or
- The other decision is the most recent authority available on the issue at hand.
