Case law is often referred to as common law in many regions of the world, and is also known as judge-made law. This latter term derives from the fact that, while legislation is technically passed in most countries by a separate legislative branch, courts are able to exercise a moderate amount of quasi-legislative power through the use of precedent and case law. Case law is viewed by most people as a crucial part of a functioning judiciary, as it allows for courts to transform decisions that may have taken a great deal of time and energy to arrive at into a sort of de facto law, making future cases much easier to decide.

In some cases, a judge may intentionally go against established case law in an effort to begin the process of re-examining a precedent and perhaps ultimately changing it. This often happens with precedents in case law that a judge may consider out-dated or irrelevant in the contemporary climate. By issuing a decision that the judge knows will be appealed, he or she pushes the case into higher courts where the old established precedents may be overturned in favor of a new outlook.