A statute of limitations is a law passed by a legislative body in a common law system to set the maximum time after an event within which legal proceedings may be initiated.
When the period of time specified in a statute of limitations passes, a claim might no longer be filed, or, if filed, may be liable to be struck out if the defense against that claim is, or includes, that the claim is time-barred as having been filed after the statutory limitations period. When a statute of limitations expires in a criminal case, the courts no longer have jurisdiction. Most crimes that have statutes of limitations are distinguished from serious crimes as these may be brought at any time.
In civil law systems, similar provisions are typically part of their civil or criminal codes and known collectively as periods of prescription. The cause of action dictates the statute of limitations, which can be reduced (or extended) to ensure a fair trial. The intention of these laws is to facilitate resolution within a "reasonable" length of time. What period of time is considered "reasonable" varies from country to country, and within countries such as the United States from state to state. Within countries and states, the statute of limitations may vary from one civil or criminal action to another. Some nations have no statute of limitations whatsoever.
Analysis of a statute of limitations also requires the examination of any associated statute of repose, tolling provisions, and exclusions.