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Delegated legislation is law made by ministers under powers given to them by Acts of Parliament. Reasons for the use of delegated, rather than primary legislation, may include:

  • providing for the technical implementation of a policy;
  • filling in detail that may need to be updated frequently or is otherwise subject to change; and
  • accommodating cases where the detailed policy has to work in different circumstances.

This briefing provides an overview of how scrutiny of delegated legislation takes place in both Houses and considers the impact of Brexit on it.

Individual pieces of delegated legislation are often called secondary legislation to distinguish them from primary legislation contained in Acts of Parliament. Statutory instruments (SIs) are the most frequently used type of delegated legislation. Parliamentary scrutiny of secondary legislation most commonly takes the form of negative or affirmative procedures.

Brexit has posed legislative challenges. Several parliamentary committees have expressed concern that the volume and scope of secondary legislation necessary to implement the UK’s withdrawal from the EU would be substantial. Initial government estimates were that between 800 and 1,000 statutory instruments would be required, although this number has been revised down to approximately 600 SIs.

Amendments were agreed during the passage of the European Union (Withdrawal) Bill to introduce a sifting function in both the Lords and the Commons. This applies to SIs made under certain sections of the act that the has Government proposed should be subject to the negative procedure; each committee (European Statutory Instruments Committee in the Commons, the Secondary Legislation Scrutiny Committee in the Lords) can recommend that the SI would instead be more appropriately subject to the affirmative procedure.

On 27 March 2019, the House of Lords approved regulations, required to amend in UK law ‘the exit day’ specified in the European Union (Withdrawal) Act, to reflect agreement reached with the European Union to extend the two-year article 50 period beyond 29 March 2019.


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