Case law is a discipline of law that is based on judicial decisions as opposed to law based on statutes, regulations, or other sources. It also refers to the collection of judicial decisions within a given jurisdiction dealing with a specific issue or topic. Case law is also referred to as precedent or common law and provides judges the body of previous decisions to decide issues before them. It can either be binding law or simply persuasive in nature such as when the US Court of Appeals for the Fifth Circuit makes a decision, and a court sitting in California (whether it is a federal or state) does not necessarily have to abide by that law or principle.
Courts in the United States adhere to a principle known as stare decisis which refers to the fact that courts will generally respect and adhere to the precedents of previous decisions. A court, however, does not have to abide by a decision that is not a binding precedent. Courts will typically follow the decisions of higher courts within their jurisdictions. A United States Supreme Court decision is a binding precedent in all US courts.
An understanding of case law results from insight into the judicial process and how cases are brought forth to court systems. Cases begin the adjudication process at the trial court level where they could be decided as trial by judge or trial by jury. At the trial court level, evidence and witnesses are presented. The United States has 94 district or trial courts that resolve disputes by determining the facts and applying legal principles to reach a verdict. An appellate court or appeals court will hear appeals from parties who wish to change the results of the case heard before the trial court. The appeals court will generally not review the evidence in a given case but will instead rule on any legal issues that the case presents. There are 13 appellate courts sitting below the US Supreme Court, divided into 12 regional circuits which all have a court of appeals.
State courts try the majority of all civil and criminal cases and local magistrates can sit on county or district courts. One appeal is always granted for decisions regarding specific cases, but two levels of appeal exist in many states. Most federal law is statutory and enforced by federal courts, and the US Supreme Court is the authority for determining whether legislation passed by a jurisdiction or state complies with what has been set forth in the US Constitution.
Case law has been applied to a variety of cases including those involving human trafficking, human rights, employment issues, environmental cases, and criminal cases. Many universities provide resources to search for specific cases in a given area of focus and have online law libraries providing information about different cases. Information from specific cases can redefine previously binding precedent such as when the Supreme Court evaluates issues set before them.
For students in various parts of the world, there are good case law tutorials available, including ones from the Georgetown University Law Center, University of Canterbury, University of Wollongong, and Elsevier.