Stare decisis is a legal principle which dictates that courts cannot contravene precedent. They must uphold prior decisions, to literally “stand by previous decisions.” Many legal system include the doctrine of stare decisis in their legal structure and this doctrine can be applied to many different types of cases. Some people have criticized the adherence to precedent, arguing that it has some clear flaws, including the fact that setting precedent can sometimes involve contravening previous precedent, which means that there would be no precedent to follow if judges were never willing to go against older legal decisions.
The concept of stare decisis can manifest in two different ways. In the first case, lower courts are expected to abide by rulings from higher courts. If a higher court has established a precedent in a similar case, the lower court must follow the decision entered by the higher court. If it wishes to go against the precedent set by the upper court, the lower court must be able to demonstrate that the decision contradicts the law or is unjust in some way.
Courts are also expected to abide by precedents set in that court before, whether the court involved is lower or higher. The interpretation of the law should remain reasonably consistent through time and stare decisis reminds courts that they have an obligation to uphold their own prior decisions. Again, the validity of a decision may be challenged for the purpose of overruling it and setting a new precedent.
The obvious problem with stare decisis is that if a previous judicial decision is unfair, it must be overturned in order to set a new precedent. The infamous “separate but equal” doctrine in the United States is a good example of this situation. This doctrine was used to support the legality of segregation. Later, the court recognized that this doctrine was in fact not fair, and did not abide by the spirit of the Constitution. As a result, it was overturned to rule that segregation was not legal. If the court had stuck strictly with stare decisis, any challenge to segregation would have been struck down in accordance with the prior separate but equal ruling.
This doctrine is designed to keep courts consistent. Stare decisis can also help courts avoid politicization, because it allows them to focus on enforcing the law as it is currently understood, rather than responding to cases in accordance with current political fads.