Advantages
Time: The requirement for new law to be made is often a very slow process, this is not suitable in times of emergency. For example, to strengthen the Anti Terrorism, Crime and Security Act 2001 in a number of ways necessary to counter the increased threat to the UK etc. In response to such emergencies delegated legislation is able to introduce change quickly and effectively
Specialist Or Local Knowledge:
Members of Parliament often may not posses an adequate level of specialist technical or local knowledge. Delegated legislation however, allows for the necessary information and knowledge to be gathered and properly used. For example, 1before any new revised police Code of Practise under the Police and criminal Evidence Act 1984 is issued, their must be consultation with a wide range of people including persons representing the interest of police authorities, the General Council of the bar and the law society.
Flexibility:
Because of unknown circumstances, delegated legislation can provide continuous alterations to the enabling Act, ensuring the law is current and up to date.
Disadvantages
Democratic Involvement:
One criticism of Delegated Legislation is that the law making powers are usually passed to un-elected permanently employed Civil Servants and not scrutinised, controlled or debated by elected Members of Parliament. This has long been recognised, and was one of the major concerns expressed by 2Hewert in The New Despotism (1929) and by the Donoughmore Report on ministers’ powers (1932).
Lack OF Publicity:
There is very little publicity with regards to Delegated Legislation. The general public are often unaware of new laws being made or existing laws being changed. Partly due to the fact that Delegated Legislation is not debated by Parliament, therefore the press do not have the opportunity to raise public awareness as they would with an Act of Parliament.
Judicial Control:
Delegated Legislation can potentially be used in ways that Parliament did not intend, and can therefore go beyond the powers conferred, Ultra Vires. There are two types, Procedural where ministers don’t follow the correct procedures when making delegated legislation, for example 3The Aylesbury Mushroom case 1972 and Substantive when the validation of the delegated legislation may be challenged. For example, that the use of delegated power exceeds that anticipated by law 4Attorney-general v Fulham Corporation (1921).
Updated 19 March 2026
This article provides a basic introductory overview of delegated legislation and remains broadly accurate as a starting point for students. However, several points should be noted.
The legal principles described — including the advantages of speed and specialist knowledge, the disadvantages of limited democratic scrutiny and publicity, and the doctrine of ultra vires with its procedural and substantive limbs — remain accurate statements of general constitutional and administrative law.
The cases cited (Attorney-General v Fulham Corporation [1921] and the Aylesbury Mushroom case, Agricultural, Horticultural and Forestry Industry Training Board v Aylesbury Mushrooms Ltd [1972]) remain valid illustrations of ultra vires, though students should be aware that the case law on judicial review of delegated legislation has developed considerably since these decisions. Modern administrative law, including grounds of review under Associated Provincial Picture Houses Ltd v Wednesbury Corporation [1948] and the broader framework established in cases such as Council of Civil Service Unions v Minister for the Civil Service [1985], is not addressed and would be relevant to a fuller treatment of judicial control.
The reference to the Anti-Terrorism, Crime and Security Act 2001 as a contemporary example of emergency legislation is now dated. Students should note that more recent examples include the extensive use of delegated legislation during the COVID-19 pandemic under the Public Health (Control of Disease) Act 1984, which generated significant academic and parliamentary debate about the adequacy of democratic scrutiny of delegated powers — directly relevant to the disadvantages discussed in this article.
The Police and Criminal Evidence Act 1984 remains in force and Codes of Practice under it continue to be revised, so that example remains accurate in principle, though the consultation framework has evolved.
The article does not address the Retained EU Law (Revocation and Reform) Act 2023, which granted extensive delegated powers to ministers to restate, revoke or replace retained EU law — a significant recent development in the delegated legislation landscape that students at any level should be aware of.
Overall, this article is suitable only as a very introductory outline and should be supplemented with up-to-date materials, particularly given developments since 2020.
