Stare decisis is a legal principle by which judges are obliged to respect the precedent established by prior decisions. The words originate from the phrasing of the principle in the Latin maxim Stare decisis et non quieta movere: “whatever has been decided must stand”. In a legal context, it means that courts should generally abide by precedent and not disturb settled matters. However, this doctrine has been overruled by courts in some cases. International trade laws have not always followed prevous decisions and thus might produce inconsistent decisions. Basically this legal principle states that once a law has been determined by the appellate court to be relevant to the facts of the case, future cases will follow the same principle of law if they involve considerably identical facts.
The principle of stare decisis was not always applied with uniform strictness. In medieval England, common-law courts looked at earlier cases for guidance, but they could reject those they considered bad law. Courts also relied less on previous decisions because there was a lack of reliable written reports of cases. Official reports of cases heard in various courts began to appear in the United States in the early 1800s, but semi-official reports were not produced in England until 1865. When published reports became available, lawyers and judges finally had direct access to cases and could more accurately interpret prior decisions. American law operates under the doctrine of stare decisis,which means that prior decisions should be maintained — even if the current court would otherwise rule differently — and that lower courts must abide by the prior decisions of higher courts.
The idea is based on a belief that government needs to be relatively stable and predictable. This means that overturning a Supreme Court decision is very difficult. There are two ways it can happen: * States can amend the Constitution itself. This requires approval by three-quarters of the state legislatures — no easy feat. However, it has happened several times. * The Supreme Court can overrule itself. This happens when a different case involving the same constitutional issues as an earlier case is reviewed by the court and seen in a new light, typically because of changing social and political situations.
The longer the amount of time between the cases, the more likely this is to occur (partly due to stare decisis). The doctrine , thus allows summary repulsion of claims upon which the court has already decided earlier .The concept generally applies to the highest court of a country like the House of Lords of U.K (as it was earlier) -In Union of India & Anr. v. Paras Laminates (P) Ltd, (1990) 4 SCC 453 at pg. 457, this Court observed as under :- “. It is true that a bench of two members must not lightly disregard the decision of another bench of the same Tribunal on an identical question. This is particularly true when the earlier decision is rendered by a larger bench. The rationale of this rule is the need for continuity, certainty and predictability in the administration of justice. Persons affected by decisions of tribunals or courts have a right to expect that those exercising judicial functions will follow the reason or ground of the judicial decision in the earlier cases on identical matters”. It has been stated that in the absence of a strict rule of precedent, litigants would take every case to the highest court, in spite of a ruling to the contrary, in the hope that the decision may be overruled.
-In Hari Singh v. State of Haryana, (1993) 3 SCC 114, at page 120, this Court stated the importance of consistent opinions in achieving harmony in Judicial System: “ It is true that in the system of justice which is being administered by the courts, one of the basic principles which has to be kept in view, is that courts of coordinate jurisdiction, should have consistent opinions in respect of an identical set of facts or on a question of law. If courts express different opinions on the identical sets of facts or question of law while exercising the same jurisdiction, then instead of achieving harmony in the judicial system, it will lead to judicial anarchy.”
Until 1966, the House of Lords in the United Kingdom was bound to follow all of its previous decisions under the principle of stare decisis, even if this created “injustice” and “unduly restrict(s) the proper development of the law” (London Tramways Co. v London County Council  AC 375). The Practice Statement 1966 is authority for the House of Lords to depart from their previous decisions. It does not affect the precedential value of cases in lower courts; all other courts that recognise the Supreme Court(formerly the House of Lords)as the [court of last resort] are still bound by Supreme Court decisions. Before this, the only way a binding precedent could be avoided was to create new legislation on the matter.