Statutory instruments are the most frequently used type of secondary legislation, with approximately 3,500 made each year, although only about 1,000 need to be considered by Parliament.
Delegated legislation is dependent on its parent act, which prescribes its parameters and procedures.
Although a large volume of delegated legislation is written without close parliamentary scrutiny, there are statutory instruments to prevent its misuse.
Delegated legislation saves parliamentary time by considering matters of technical detail.
A statutory instrument related to the parent act is required to write delegated legislation.
Clauses may be grouped under headings and in complex delegated legislation, the document may be divided into parts.
By convention, the House of Lords will not veto but rather pass a motion to convey its concerns about the legislation.
Delegated legislation can be quashed by a court if it is found to be ultra vires (outside the parameters defined in the parent act).
In "substantive ultra vires", delegated legislation is deemed void because it goes beyond the powers defined in the parent act.