Most delegated legislation in Great Britain is made in the form of a Statutory Instrument. (In Northern Ireland, delegated legislation is organised into Statutory Rules, rather than Statutory Instruments.) The advent of devolution in 1999 resulted in many powers to make Statutory Instruments being transferred to the Scottish Government and Welsh Assembly Government, and oversight to the Scottish Parliament and National Assembly for Wales. Instruments made by the Scottish Government are now classed separately as Scottish Statutory Instruments.
A Statutory Instrument is used when an Act of Parliament passed after 1947 confers a power to make, confirm or approve delegated legislation on:
Minister of the Crown includes the Welsh Ministers and various Acts provide that delegated legislation, although made by another person (for example, the General Dental Council), is also to be made by Statutory Instrument.
Use of a Statutory Instrument is not required where the parent Act does not specify it. This may be the case where delegated legislation is of only limited application and therefore not of general importance. Instead, other provisions may be made for publishing the legislation. So, for example, an Order providing for the transfer of contracts from one National Health Service body to another may only be notified to the affected bodies, and by-laws made by a local council may be publicised through an announcement in local newspapers.
The main effect of delegated legislation being made by Statutory Instrument is that as soon as it is made it is numbered, catalogued, printed, made available for sale and published on the internet. This ensures that the public has easy access to the new laws.
Numbers are assigned by Her Majesty's Stationery Office and are sequential within the year of making. The number provides a means of citing the Statutory Instrument in addition to the title given by the Instrument itself. So, for example, The Income Tax (Exemption of Minor Benefits) (Amendment) Regulations 2003 are numbered and may be cited as SI 2003 No. 1434 or SI 2003/1434.
In addition to the main numbering system, there are a number of subsidiary numbering systems which may indicate an Instrument's position within a particular series of Instruments (in the following list n indicates the number):
Statutory Instruments will be classified by subject heading in the annual edition printed by Her Majesty's Stationery Office.
Printed copies of a Statutory Instrument will generally be on sale within a week of the date it is made.
Most Statutory Instruments (SIs) are subject to one of two forms of control by Parliament, depending on what is specified in the parent Act.
There is a constitutional convention that the House of Lords does not vote against delegated legislation. It should be noted that Parliament's control is limited to approving, or rejecting, the Instrument as laid before it: it cannot (except in very rare cases) amend or change it.