Statutes of limitations are laws passed by legislative bodies in common law systems 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 to that claim is, or includes, that it is statute barred as having been filed after the limitations period.
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, and within countries and states from civil or criminal action to civil or criminal action. Some countries, and some crimes (depending on the country), have no statute of limitations whatsoever. 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.
When a statute of limitations expires in a criminal case, the courts no longer have jurisdiction. Analysis of a statute of limitations includes the examination of any associated statute of repose, tolling provisions, and exclusions.
Common law legal systems can include a statute specifying the length of time within which a claimant or prosecutor must file a case. In some civil jurisdictions (e.g., California), a case cannot begin after the period specified, and courts have no jurisdiction over cases filed after the statute of limitations has expired. In some other jurisdictions (e.g., New South Wales, Australia), a claim can be filed which may prove to have been brought outside the limitations period, but the court will retain jurisdiction in order to determine that issue, and the onus is on the defendant to plead it as part of their defence, or else the claim will not be statute barred.
Once filed, cases do not need to be resolved within the period specified in the statute of limitations.
The purpose and effect of statutes of limitations are to protect defendants. There are three reasons for their existence:
The limitation period generally begins when the plaintiff's cause of action accrues, or they become aware of a previous injury (for example, occupational lung diseases such as asbestosis). In Classical Athens, a five-year statute of limitations was established for all cases except homicide and the prosecution of non-constitutional laws (which had no limitation). Demosthenes wrote that these statutes of limitations were adopted to control "sycophants" (professional accusers).