Most of the UK’s law is made not via Acts passed through Parliament  but instead via delegated legislation. This means that Parliament will pass an Act with a framework for a policy idea or law but the delegated legislation will be used subsequently, to fill out the precise details of the law. The most common form of delegated legislation is a Statutory Instrument.

The content of Statutory Instruments is normally prepared by Government Departments and this means that the Government can fill out the details of primary legislation or sometimes even change primary legalisation without having to pass another Act through Parliament. Delegated legislation is necessary to regulate modern British society, it would be impossible for Parliament to pass all the laws written via delegated legislation in ordinary Parliamentary sessions. Each year delegated legislation exceeds primary legislation by between two and five times.

However, for as long as delegated legislation has existed there have been concerns about the way it is used.  Sometimes the Government leaves difficult and controversial matters of policy to Statutory Instruments so that the Government can avoid the difficulties of having to pass a law through both houses of Parliament. For example in 2015, the Government attempted to use its delegated powers under the Tax Credits Act 2002 to draft Statutory Instruments reducing the threshold for when  an individual was entitled to a tax credit.

Another problem is that unlike primary legislation, Statutory Instruments are almost never debated on the floor of the House of Commons and less than 0.001 Statutory Instruments have ever been voted down by Parliament

Statutory Instruments can be laid by either the negative or affirmative resolution procedure. If a Statutory Instrument is laid as a negative instrument then it is presented to Parliament and if no member votes to annul it in the following 40 days then it becomes law. If a Statutory Instrument is laid as an affirmative instrument then a Committee  in each of the House of Lords and Commons must debate and approve it before it becomes law. Committees however, are  generally only made up of 15 members of Parliament in comparison to primary legislation which is debated on the floor of the House of Commons.

More information about Statutory Instruments, and difficulties with the way they are presently used, can be found on the Hansard Society’s Website and  in its 2014 Publication “The Devil is in the Detail”.