Stare decisis

Stare decisis (from the Latin phrase Stare decisis et non quieta movere, "Maintain what has been decided and do not alter that which has been established") is the legal principle by which judges are obliged to obey the precedents established by prior decisions.

In the United States, which uses a common law system in its federal courts and most of its state courts, the Ninth Circuit Court of Appeals has stated:

Stare decisis is the policy of the court to stand by precedent; the term is but an abbreviation of stare decisis et quieta non movere — "to stand by and adhere to decisions and not disturb what is settled." Consider the word "decisis." The word means, literally and legally, the decision. Nor is the doctrine stare dictis; it is not "to stand by or keep to what was said." Nor is the doctrine stare rationibus decidendi — "to keep to the rationes decidendi of past cases." Rather, under the doctrine of stare decisis a case is important only for what it decides — for the "what," not for the "why," and not for the "how." Insofar as precedent is concerned, stare decisis is important only for the decision, for the detailed legal consequence following a detailed set of facts.

In other words, stare decisis applies to the holding of a case, rather than to obiter dicta. As the United States Supreme Court has put it: "dicta may be followed if sufficiently persuasive but are not binding."

The doctrine that holdings have binding precedential value is not valid within most civil law jurisdictions as it is argued that this principle interferes with the right of judges to interpret law and the right of the legislature to make law. Most such systems, however, recognize the concept of jurisprudence constante, which argues that even though judges are independent, they should judge in a predictable and non-chaotic manner. Therefore, judges' right to interpret law does not preclude the adoption of a small number of selected binding case laws.

Principle
The principle of stare decisis can be divided into two components. The first is the rule that a decision made by a superior court is binding precedent (also known as mandatory authority) which an inferior court cannot change. The second is the principle that a court should not overturn its own precedents unless there is a strong reason to do so and should be guided by principles from lateral and inferior courts. The second principle, regarding persuasive precedent, is an advisory one which courts can and do ignore occasionally. Kmiec, Keenan. The Origin and Current Meanings of "Judicial Activism", California Law Review (2004):

Some instances of disregarding precedent are almost universally considered inappropriate. For example, in a rare showing of unity in a Supreme Court opinion discussing judicial activism, Justice Stevens wrote that a circuit court "engaged in an indefensible brand of judicial activism" when it "refused to follow" a "controlling precedent" of the Supreme Court. The rule that lower courts should abide by controlling precedent, sometimes called "vertical precedent," can safely be called settled law. It appears to be equally well accepted that the act of disregarding vertical precedent qualifies as one kind of judicial activism. "Horizontal precedent," the doctrine requiring a court "to follow its own prior decisions in similar cases," is a more complicated and debatable matter....[A]cademics argue that it is sometimes proper to disregard horizontal precedent. Professor Gary Lawson, for example, has argued that stare decisis itself may be unconstitutional if it requires the Court to adhere to an erroneous reading of the Constitution. "If the Constitution says X and a prior judicial decision says Y, a court has not merely the power, but the obligation, to prefer the Constitution." In the same vein, Professors Ahkil Amar and Vikram Amar have stated, "Our general view is that the Rehnquist Court's articulated theory of stare decisis tends to improperly elevate judicial doctrine over the Constitution itself." It does so, they argue, "by requiring excessive deference to past decisions that themselves may have been misinterpretations of the law of the land." For Lawson, Akhil Amar, and Vikram Amar, dismissing erroneous horizontal precedent would not be judicial activism; instead, it would be appropriate constitutional decisionmaking.---Walton Myers

Vertical stare decisis
Generally, a common law court system has trial courts, intermediate appellate courts and a supreme court. The inferior courts conduct almost all trial proceedings. The inferior courts are bound to obey precedents established by the appellate court for their jurisdiction, and all supreme court precedent.

The Supreme Court of California's explanation of this principle is that

"[u]nder the doctrine of stare decisis, all tribunals exercising inferior jurisdiction are required to follow decisions of courts exercising superior jurisdiction. Otherwise, the doctrine of stare decisis makes no sense. The decisions of this court are binding upon and must be followed by all the state courts of California. Decisions of every division of the District Courts of Appeal are binding upon all the justice and municipal courts and upon all the superior courts of this state, and this is so whether or not the superior court is acting as a trial or appellate court. Courts exercising inferior jurisdiction must accept the law declared by courts of superior jurisdiction. It is not their function to attempt to overrule decisions of a higher court."

Appellate courts are only bound to obey supreme court decisions. The application of the doctrine of stare decisis from a superior court to an inferior court is sometimes called vertical stare decisis.

However, in Federal systems the division between Federal and local law may result in complex interactions. For example, state courts in the United States are not considered inferior to Federal courts but rather constitute a parallel court system. While state courts must defer to federal courts on issues within federal jurisidiction such as constitutional issues, federal courts must defer to state courts on issues of state law.

Horizontal stare decisis
The idea that a judge is bound by (or at least should respect) decisions of earlier judges of similar or coordinate level is called horizontal stare decisis.

In the United States federal court system, the intermediate appellate courts are divided into "circuits". Each panel of judges on the court of appeals for a circuit is bound to obey the prior appellate decisions of the same circuit. Precedents of a United States court of appeals may be overruled only by the court en banc, that is, a session of all the active appellate judges of the circuit, or by the United States Supreme Court.

When a court binds itself, this application of the doctrine of precedent is sometimes called horizontal stare decisis. The State of New York has a similar appellate structure as it is divided into four appellate departments supervised by the final New York State Court of Appeals. Decisions of one appellate department are not binding upon another, and in some cases the departments differ considerably on interpretations of law.

The last resort and strict stare decisis
The British House of Lords was not strictly bound to always follow its own decisions until the case London Street Tramways v London County Council [1898] AC 375. After this case, once the House had given a ruling on a point of law, the matter was closed unless and until Parliament made a change by statute. This is the most strict form of the doctrine of stare decisis. (One not applied, previously, in common law jurisdictions, where there was somewhat greater flexibility for a court of last resort to review its own precedents.)

This situation changed, however, after the issuance of the Practice Statement of 1966. It enabled the House of Lords to adapt English law to meet changing social conditions. In R v G & R 2003, the House of Lords overruled its decision in Caldwell 1981, which had allowed the House to establish mens rea ("guilty mind") by measuring a defendant's conduct against that of a "reasonable person," regardless of the defendant's actual state of mind.

However, the Practice Statement has been seldom applied by the House of Lords, usually only as a last resort. As of 2005, the House of Lords has rejected its past decisions no more than 20 times. They are reluctant to use it because they fear to introduce uncertainty into the law. In particular, the Practice Statement stated that the Lords would be especially reluctant to overrule themselves in criminal cases because of the importance of certainty of that law. The first case involving criminal law to be overruled with the Practice Statement was Anderton v Ryan (1985), which was overruled by R v Shivpuri (1986), two decades after the Practice Statement. Remarkably, the precedent overruled had been made only a year before, but it had been criticised by several academic lawyers. As a result, Lord Bridge stated he was "undeterred by the consideration that the decision in Anderton v Ryan was so recent. The Practice Statement is an effective abandonment of our pretention to infallibility. If a serious error embodied in a decision of this House has distorted the law, the sooner it is corrected the better." Still, the House of Lords has remained reluctant to overrule itself in some cases; in R v Kansal (2002), the majority of House members adopted the opinion that R v Lambert had been wrongly decided, but declined to depart from their earlier decision.

Application to the U.S. legal system
In the United States Supreme Court, the principle of stare decisis is most flexible in constitutional cases:


 * Stare decisis is usually the wise policy, because in most matters it is more important that the applicable rule of law be settled than that it be settled right.... But in cases involving the Federal Constitution, where correction through legislative action is practically impossible, this Court has often overruled its earlier decisions.... This is strikingly true of cases under the due process clause. Burnet v. Coronado Oil & Gas Co., 285 U.S. 393, 406–407, 410 (1932) (Brandeis, J., dissenting).

For example, in the years 1946–1992, the U.S. Supreme Court reversed itself in about 130 cases. The U.S. Supreme Court has further explained as follows:
 * [W]hen convinced of former error, this Court has never felt constrained to follow precedent. In constitutional questions, where correction depends upon amendment, and not upon legislative action, this Court throughout its history has freely exercised its power to reexamine the basis of its constitutional decisions. Smith v. Allwright, 321 U.S. 649, 665 (1944).