Updated October 28, 2020:

What is a Precedent?

Precedent is a legal principle, created by a court decision, which provides an example or authority for judges deciding similar issues later. Generally, decisions of higher courts (within a particular system of courts) are mandatory precedents on lower courts within that system. That means the principle announced by a higher court must be followed in later cases.

For example, the California Supreme Court decision that unmarried people who live together may enter into cohabitation agreements (Marvin v. Marvin), is binding in all appellate courts and trial courts in California (which are lower courts in relation to the California Supreme Court). Similarly, decisions of the U.S. Supreme Court (the highest court in the country) are generally binding on all other courts in the U.S.

Decisions of lower courts are not binding on higher courts, although from time to time a higher court will adopt the reasoning and conclusion of a lower court. Decisions by courts of the same level (usually appellate courts) are considered persuasive authority. That is, they should always be carefully considered by the later court but need not be followed.

Facts About Precedents

As a practical matter, courts can usually find precedent for any direction they want to go in deciding a particular case. Accordingly, precedent is used often to justify a particular outcome in a case as it is used to guide the decision. The body of judicial decisions includes the points used to formulate and decide a case in a court of law.

A previously decided case is considered binding in the court where it was issued and in all lower courts in the same jurisdiction. Precedents are used when a court decision in an earlier case has similar facts and laws to a dispute currently before a court. Precedent will ordinarily govern the decision of a later similar case unless a party can show that it was wrongly decided or that it differed in some significant way.

A precedent can be used in a decision of courts of justice when exactly in point with a case before the court is generally held. They have binding authority, as well to keep the scale of justice even and steady because the law, in that case, has been solemnly declared and determined.

Validating a Precedent

To render precedents valid, they must:

  • Be founded in reason and justice
  • Have been made upon the argument, and be the solemn decision of the court.
  • There must be a current decision to give them a binding effect,

According to Lord Talbot, it is "much better to stick to the known general rules than to follow any one particular precedent which may be founded on reason unknown to us." Blackstone says that a former decision is, in general, to be followed unless "manifestly absurd or unjust," and, in the latter case, it is declared when overruled not that the former sentence was bad law, but that it was not law.

When Are Precedents Useful?

Precedents can only be useful when they show that the case has been decided upon a certain principle and ought not to be binding when contrary to such a principle. If a precedent is to be followed because it is a precedent, even when decided against an established rule of law, there can be no possible correction of abuses because the fact of their existence renders them above the law. It is always safe to rely on principles.

"In Law, a previous decision, rule or practice which, in the absence of a definite statute, has whatever force and authority a Judge may choose to give it, thereby greatly simplifying his task of doing as he pleases. As there are precedents for everything, he has only to ignore those that make against his interest and accentuate those in the line of his desire. Invention of the precedent elevates the trial-at-law from the low estate of a fortuitous ordeal to the noble attitude of a dirigible arbitrament." -- Ambrose Bierce