What Is A Sunset Clause?

A sunset clause is when a parliament, a national assembly or any other legislature passes a bill, which includes a date when the act will automatically expire. It is especially common for laws to be passed with sunset clauses when they are deemed to be controversial for any reason, or if any part of the bill may potentially include the curtailment of civil liberties. It is certainly possible for a parliament to extend a piece of legislation which contains a sunset clause, but failing this the bill will automatically expire.

The most recent example of a major piece of legislation expiring due to a sunset clause were Canada's anti-terror laws. They were introduced by Prime Minister Jean Chrétien's Liberal government following the September 11, 2001 terrorist attacks on the United States. The most controversial aspect of the bill permitted police to detain people suspected of terrorist activities for up to 72 hours without charging them.

The law expired on 1 March 2007 thanks to a sunset clause. While the minority Conservative government supported an extension, all opposition parties rejected this idea.