Sunset clause

In public policy, a sunset provision or clause is a measure within a statute, regulation or other law that provides that the law shall cease to have effect after a specific date, unless further legislative action is taken to extend the law. Most laws do not have sunset clauses and therefore remain in force indefinitely, except under systems in which desuetude applies.

The roots of sunset provisions are laid in Roman law of the mandate. At the time of the Roman Republic, the empowerment of the Roman Senate to collect special taxes and to activate troops was limited in time and extent. Those empowerments ended before the expiration of an electoral office, such as the Proconsul. The rule Ad tempus concessa post tempus censetur denegata is translated as "what is admitted for a period will be refused after the period". The same rules were applied in the Roman emergency legislation. The fundamental principle appeared in several areas of legislation and later codified in the Codex Iustinianus (10, 61, 1). The principle was broken when Julius Caesar became dictator for life.

Sunset provisions have been used extensively throughout legal history. The idea of general sunset provisions was discussed extensively in the late 1970s.

In American federal law parlance, legislation that renews an expired mandate is a reauthorization act or extension act. Extensive political wrangling often precedes reauthorizations of controversial laws or agencies. High-profile examples in American law include:

Part of the Alien and Sedition Acts, the Sedition Act was a political tool used by John Adams and the Federalist Party to suppress opposition. The authors ensured the act would terminate at the end of Adams' term so that it could not be used by Democratic-Republicans against his own party.

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