As well as Acts of Parliament, United Kingdom law is also made through Statutory Instruments (SIs) (also referred to as delegated, or secondary legislation). These are laws which are written by a Government minister, exercising legislative powers delegated to him or her by Act of Parliament. Some of these must be approved by Parliament before they can become law, others need only be laid before Parliament a certain number of days (usually 40) before coming into force. The section of the Act of Parliament that grants the power will usually state which of the two is to apply. Generally, if it is a potentially contentious power the positive approval route will be required, and if not, the negative route.
Statutory Instruments are not the same thing as an Order in Council: Statutory Instruments are 'delegated legislation' (the power is delegated by Parliament), whereas Orders in Council operate through the Royal Prerogative.
They are used because they are much faster and simpler to implement than a full Act of Parliament. SIs are sometimes described as "secondary legislation, not second class legislation". They have the same force as an Act of Parliament, and much of the U.K.'s law is made in this way. There are literally thousands of SIs each year, compared with a few dozen Acts.
Probably one of the biggest uses of Statutory Instruments is incorporating into UK law provisions of Directives of the EU, which are brought in under the provisions of the Single European Act.
They are also used to bring Acts of Parliament into force: it is not uncommon for quite major pieces of legislation to be passed by Parliament with all the clauses 'turned off', and a power for the Minister to 'turn them on' (or 'bring into force' as it is properly called) at a later date. Some sections are never brought into force at all.
Canada also uses the Statutory Instrument nomenclature. An example being the Proclamation of the Queen of Canada on April 17, 1982 bringing into force the Constitution Act, 1982 also known as the Canada Act 1982 (U.K.).
- All United Kingdom Acts of Parliament from 1988 onwards and Statutory Instruments from 1987 onwards are available free on-line under Crown copyright terms from Her Majesty's Stationary Office (HMSO) at http://www.hmso.gov.uk/
- List of Canadian Statutory Instruments (http://laws.justice.gc.ca/en/index/index.html)