Legislation: Statutory Instruments made simple

Added: 13 May 2009

When the public think of Parliament’s role in passing laws, they tend to think of this in terms of sweeping Acts of Parliament.  However, these Acts create powers to pass other laws, many of which receive no scrutiny at all on the floor of the House.  They are surprisingly little-known given that about three and a half thousand are published each year, and they are called Statutory Instruments (SIs), also known as delegated or secondary legislation.  Those that are considered are brought before a Delegated Legislation (DL) Committee, and researchers will often only come across them when their bosses are nominated to sit on such a committee.

This guide aims to uncover some of the mystery surrounding SIs and suggest some tips for providing a decent briefing for the boss when the summons arrives to attend a DL committee.


  1. What is an SI?
  2. Main types of SI
  3. Keeping track of SIs
  4. Delegated Legislation Committees
  5. Preparing for a debate
  6. More information on SIs

1.  What is an SI?

As pieces of delegated legislation, SIs (Statutory Instruments) are sets of regulations that each stem from a ‘parent’ or ‘enabling’ Act (the primary legislation) and comprise all the fiddly bits that were glossed over in the Act itself.

So if the Fruit On The Tube Act 2020 states that apiece of fruit will be given free to every traveller on the Northern Line, there might be an SI, the Fruit On The Tube (Banana) SI put down in 2022 to state that the piece of fruit given out can include a banana, despite its technical classification as a herb. You get the picture.

They are used to ensure that a Bill passes smoothly through Parliament and does not get bogged down in a mass of technical details, which can be worked out in regulations afterwards. Some of the more technical bills are peppered with references to ‘regulations’: the Welfare Reform Act refers to them 387 times in its 114 pages.

Regulations are also very useful fillers when an issue is controversial and the Government wants a chance to think it through a bit more, and perhaps consult more widely before deciding on a firm course of action.

Or perhaps there is a developing issue that may need revising and Ministers do not want to wait for another piece of primary legislation to come forward in their Department so that they can slot the changes in.  In other words, SIs offer flexibility.

When an SI is finally laid, it could be some time since the parent Act was passed, and it can be quite daunting to work out exactly what it is and what it will do.

2.  Main types of SI 

These are two main types of SI that you are likely to come across.  Information about other types can be found by referring to the documents under “More information” below.

1) Affirmative:

SIs requiring affirmative resolution are published in draft form and require approval from both Houses before they can come into force.  They will be debated at both ends of the building, unless they relate to financial matters, which just require approval from the Commons. (NB: some SIs come into force before they are debated, but require approval to remain in force for longer than a limited period, usually 28 or 40 days).

As the Commons committees reflect the composition of the House, the Government (unless it is a minority administration) will have a majority on all Commons committees, and the last time that an SI was rejected at the Commons end was in 1969.  The Parliament Act does not apply to SIs, which means that if they are rejected by the Lords, they fall; even if the Commons has approved them.  The last set of regulations to be rejected by the Lords was the Greater London Authority (Elections Expenses) Order 2000, but as an unelected Chamber, they try not to reject too many.

2) Negative:

This type of SI does not need approval to pass into law, and is more common than those requiring the affirmative procedure.  It is published with a number (e.g. S.I., 2009, No. 615) and will simply come into force on the date stated on it, without any debate required.

If an MP or Peer has a particular objection to an SI of this type, it is possible to ‘pray against’ it and call for a debate. This has to be done within a certain time, usually 40 days from (and including) the date on which it was laid.

In the Commons, the ‘prayer’ is laid in the form of an Early Day Motion (EDM), and is often tabled in the name of an opposition party leader and the relevant spokespeople.  There is a specific wording which goes as follows:

EDM1242:  PENSIONS (S.I., 2009, No. 615)
Cameron, David

That an humble Address be presented to Her Majesty, praying that the Occupational, Personal and Stakeholder Pensions (Miscellaneous Amendments) Regulations 2009 (S.I., 2009, No. 615), dated 10 March 2009, a copy of which was laid before this House on 16 March, be annulled.

This does not guarantee a debate, but the Government may decide to arrange one, particularly if the prayer is in the name of a party leader. You will need to liaise with your Whip’s Office to see whether a debate is likely to be organised.  There is no requirement to call a vote if such a debate is granted; often MPs will simply be seeking clarification or more information about an issue.

3.  Keeping track of SIs

In order to pray against controversial SIs, you need to keep track of what is being laid. A list of SIs laid the previous day is maintained on the Parliamentary website here, in the appendices.  There is also a list here: Part 1 sets out the number of days that there are left to pray against the SI.  This period does not include periods when both Houses are adjourned for more than four days or Parliament is prorogued or dissolved.

4.  Delegated Legislation Committees

Affirmative SIs and negative SIs that are allocated a debate will be discussed for up to 90 minutes in a Delegated Legislation Committee. The Committee is usually made up of 17 Members. Other MPs may attend and speak, but only the nominated members are entitled to vote.

Unless the parent Act specifies otherwise (which is very rare), it is not possible to amend the text of an SI. It can either be approved or rejected by the Committee considering it.

The government usually set out the case for approving the instrument, and the opposition then respond. Where there is little disagreement, the item can go through very quickly (“on the nod”) – a Committee could take as little as 20 minutes.

In the Lords, SIs are usually debated on the floor of the House.

5.  Preparing for a debate

Some tips for researching the background to an SI:

  • Find the text of the Statutory Instrument and its Explanatory Memorandum (EM) online.  The EM will give you information on the purpose of the SI, the primary legislation to which it refers, the policy background as to why it is necessary, and the impact that it is expected to have.  There may also be a more detailed Impact Assessment alongside it, which is generally easier to read.
  • Find the parent Act and look up the original debate where the measure was introduced. What is the reason for bringing forward these regulations? What did your party spokesperson say at the time? The Parliament website has a useful page here that details all the stages and debates, and don’t forget to look up the relevant House of Commons Library research paper, which will summarise the key issues.
  • Find out whether the Joint Committee on Statutory Instruments or the Lords Committee on the Merits of Statutory Instruments have had anything to say about this SI.   The purpose of the Joint Committee is to ensure that SIs do not exceed the powers set out in the enabling Act, and to look at the legality of the proposals.  The Lords Committee focuses on the policy implications of the instruments.  Both committees meet weekly so keep an eye on what they are saying.
  • Has this SI already been debated in the Lords? If it is an affirmative instrument, it will need to go through both Houses (unless it is a financial measure), and it may go to the Lords first. If so, what issues were raised, and are there any that you think should receive a fuller response?
  • Has a very similar SI ever been put forward before? Search Hansard for anything similar that has gone before, as it may be that here have been many near-identical SIs amending the same primary legislation in the same way, of which this is a mere variant. For example, Double Taxation Agreements are regularly issued on individual countries, and reading the Hansard of the last debate will give you a good idea of what the main arguments in this one might be.
  • Google the title of the instrument: this often brings up background information; for example the government might have been consulting on the issue.

6.  More information on SIs

  • House of Commons Information Service factsheet here
  • House of Lords briefing on delegated legislation here
  • Library “how to” note on finding SIs here (available only if you are working within the parliamentary intranet)
  • Text of Commons Delegated Legislation Committee debates here

JEL April 2009
Updated March 2013


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