The common law system is based on the process of precedent.  In a civil trial there are two conceptual areas that must be considered; the law and the facts.  The facts are determined by a jury (or by a judge acting as the fact finder).  The meaning of the law itself is determined by the judge.  For guidance in determining the meaning of the law, the judge looks toward the precedent of prior rulings on the particular legal issue. 

Stare decisis is a concept that essentially means that courts (judges) are bound to follow the established meaning of the law. The court makes a decision about this according to how prior courts, usually a related higher level court, have ruled on the same legal issue.  The lowest level courts, the trial courts, most often follow the rule set by the courts directly above them.  If a trial court makes a decision that is contrary to the precedent, there is a strong possibility that the decision will be overturned by the higher court, the appellate court.  However, as one can observe, the law evolves and so from time to time a lower court’s decision, even though contrary to precedent, may ultimately be determined to be correct by a higher court. In such a situation, a new precedent has been set.

Appellate courts, which are above the trial courts in the hierarchy, decide legal points, but generally not factual issues.  Therefore, when you hear of a decision being overturned on appeal, it is usually means that the trial court interpreted the law inaccurately on some point.  

As mentioned before, there are state court systems and federal court systems.  Each state has its own court system according to its choice, and in consequence the state courts and their processes may vary somewhat from state to state.  These variations are sometimes the result of historic matters and tradition related to the individuality of the states.  For example, in New York the lowest level court is the Supreme Court, a naming scheme that is in contrast to most (if not all) other states –where supreme typically refers to the highest court.  There may be state procedural differences as well.  The state courts are responsible for trying matters pertaining primarily to the law of the state where they sit.

The federal courts are arranged in circuits, or federal court districts.  There are 13 circuits in the U.S., Puerto Rico and the U.S. Virgin Islands.  Because these courts are federal courts, ideally all of the circuit decisions (rulings) are in harmony with each other.  Regardless, sometimes there are discrepancies in how a particular issue is decided in one circuit versus another circuit.  When this happens the U.S. Supreme Court may decide to hear the case with the objective of creating consistent and predictable results across the circuits. However, the Supreme Court may not agree to hear the case and then the discrepancy between the circuits would remain.

The federal courts are either District Courts (trial level) or U.S. Court of Appeals.  Federal courts primarily rule on matters based in federal law or pertaining to federal issues.  There are also certain circumstances when a federal court hears a case because citizens of different states are involved, a foreign corporation is a party, the lawsuit seeks a certain (high) dollar amount, or a Constitutional right is at issue.  Some courts in the federal system focus on a specific subject matter, such as bankruptcy or patents.

The Supreme Court is the ultimate maker of precedent.  All of the other courts in the land look toward the Supreme court for the precedent and are bound to follow it as the law.  When presented with a contentious issue, the Supreme Court Justices give weight to the Court's own prior decisions as well.  A change in the law is taken as a serious matter and the Court will usually make a well considered decision before overruling its own precedent.¹

The Supreme Court decides which cases it will hear (consider) and which it will not.  This process is often by a petition for a writ of certiorari, whereby the Court is officially asked to hear the case by one of the parties involved.  When the Supreme Court rejects hearing a case, the precedent of the last court to decide the case will stand as the final result.  When such a case is rejected by the Supreme Court, a binding precedent is not established and therefore the (last) decision is seen as authoritative only in the circuit or state where it was originally decided.



Notes: 

This article is focused on primarily discussing the civil, rather than criminal, court systems.

Stare decisis is a Latin term meaning “to stand by things decided” and is “[t]he doctrine of precedent, under which it is necessary for a court to follow earlier judicial decisions when the same points arise again in litigation.” (from Black’s Law Dictionary, 8^th edition).

Resources:

View a map of the U.S. Circuit Court system: http://www.uscourts.gov/courtlinks/

More information about the Supreme Court’s role in harmonizing the circuits: http://www.uscourts.gov/outreach/resources/harmonizing.html

Text of the U.S. Constitution, Cornell University: http://www.law.cornell.edu/constitution/constitution.overview.html   ]