The principle of stare decisis, which involves precedent, obliges other courts to apply the law consistently in the same circumstances.
When a case involves the same or similar facts or the same legal issues, a judicial decision known as a precedent is used as a guide. At common law, courts must follow the precedents of other courts. Courts must follow certain precedents but not others.
Determining which decisions apply to a particular court can be difficult due to the complexity of the federal structure. Priority is usually based on several decisions. Sometimes a single decision can set a precedent. For example, a state supreme court's interpretation of an individual statute is usually considered part of the law at the outset.
