Stare Decisis

Stare decisis is a common-law concept derived from the Latin maxim Stare decisis et non quieta movere: "to stand by decisions and not disturb the undisturbed." In common law legal systems, the judiciary plays an important role in creating law and interpreting legislative enactments. Under the principal of stare decisis lower courts must follow the decisions of their supervising courts as long as the two cases are factually identical. If the lower court is unable to distinguish their case from a controlling decision, the case holding is said to be binding on the lower courts. Lawyers often take great pains to separate the holding (which is binding on lower courts) from so-called dicta (language in the decision which is not binding on lower courts).

Proponents of stare decisis argue that the system leads to greater predictability. For others, stare decisis arguably leads to the perpetuation of irrational or wrongly decided decisions. In the United States it has been said that judges use stare decisis when it follows the outcome of the case they wish to see.

The obligation to follow precedent begins with necessity, and a contrary necessity marks its outer limit. With Cardozo, we recognize that no judicial system could do society's work if it eyed each issue afresh in every case that raised it. ... Indeed, the very concept of the rule of law underlying our own Constitution requires such continuity over time that a respect for precedent is, by definition, indispensable. ... At the other extreme, a different necessity would make itself felt if a prior judicial ruling should come to be seen so clearly as error that its enforcement was for that very reason doomed.

In comparison, civil law judges are generally not constrained by the decisions of higher courts.