A government document introducing the detail of legislation. For example, ward boundary changes within a local authority will be specified in a Statutory Instrument.
In general terms, a document made under the authority, directly or indirectly, of an Act. (For more detail, see the Statutory Instruments Act 1992.)
A document issued by the delegated authority (usually a Government Minister or committee) named within an act of parliament which affects the workings of the original Act, eg The County Courts Act 1984 confers authority on to the County Court Rule Committee to make rules relating to the operation of the County Courts act
Every time minor details of an Act of Parliament needs to be changed, it can be done through a SI. When an Act is first passed, it can include clauses allowing the Government to make changes to the Act at a later stage. The laws made through these powers are also known as secondary legislation (the parent act is known as primary legislation) or delegated legislation. One example of a SI is in the fixing of fees or charges for an election, allowing these to be amended without the need for a new Bill to be passed through Parliament.
A Statutory Instrument (SI) is a form of delegated or secondary legislation in Great Britain which is governed by the Statutory Instruments Act 1946.Statutory Instruments Act 1946, section 1 Most secondary legislation in Great Britain is made in the form of a statutory instrument.