It can be a little complicated to determine whether case law is binding in a specific situation. These rules help to determine the source that you are looking for!
Cases from the higher court in the same jurisdiction are binding if they are good law.
Law is only binding when the jurisdiction and level of government are the same for the primary source and the legal issue. In short, federal courts are binding on other federal courts when they are applying federal law, and state courts are binding on the courts within the same state when they are applying state law.
Federal:
For all issues of federal law in every court, the U.S. Supreme Court is binding upon all issues of federal law.
The U.S. Supreme Court is the only court that is binding upon state courts for issues of federal law.
The U.S. Court of Appeals is can only be binding upon district courts within the same circuit.
The U.S. district courts are never binding upon any court.
State:
State courts are only binding when the court is in the same state.
The highest court in a state is binding upon all courts in the state.
The state's court of appeals is binding on the state's trial courts.
The state's trial courts are never binding.
***State court decisions are binding when the issues is of state law, even if the case is in federal court.
Case law research involves searching and retrieving legal precedent (past court decisions that became court-created law).
The purpose of a source should be distinguished before beginning research. Cases can be used as either binding authority or persuasive authority. Binding authority means that the court is bound to follow the law in the jurisdiction. Not only cases are binding, but other primary sources of law can also be binding authority. For a legal source to be binding, it must be the authoritative law in the jurisdiction and applicable to the issue of law. Persuasive sources are not binding and hold no actual power, but are included because it may be convincing to the court. Primary legal sources can be utilized as persuasive sources in jurisdictions where they are not binding.
Determine if the case is still good law!
Shepardizing or tracing a case history is important. The case history of a case needs to be checked to see if the case is good law, or if it was either overruled, reversed, or superseded. If the case has negative treatment, then the case cannot be used. It is important to note that some cases are only overruled or reversed in part so you should read carefully.
Federal Courts
U.S. Supreme Court
U.S. Court of Appeals