Due to its uncodified nature, the UK constitution is made up of numerous sources. These include the royal prerogative, conventions, common law and statute law. Whilst all these sources are important, it can undoubtedly be argued that statute law is the most significant source of the constitution. So, what is it, and why is it the case that statute law is the constitutions most important source?

What is Statute Law?

Statute Law means a law that is passed by Parliament. Whilst it is often given a singular term, there are a number of mechanisms through which statute law can be passed:

Primary Legislation – This legislation that is made via an Act of Parliament. Primary Legislation must go through the full legislative process, including through both the House of Commons and the House of Lords (unless the Parliament Act is invoked).

Secondary Legislation – This is also known as delegated legislation and is made by a person or body that has been delegated the power to do so by Parliament in primary legislation. Secondary Legislation is essential because of the amount of law that needs to be passed. It is simply not possible for Parliament to legislate through primary legislation for every decision that needs to be taken. 

Statutory Instruments – These are the most common way that secondary legislation is passed with around 3,500 being passed per year.

Whilst these are all different mechanisms, they are all encompassed under the heading of statute law and all must be enabled by primary legislation.

How does the legislative process work?

All primary legislation is passed in the same way, regardless of what is it about. This differs from countries like the US where certain fundamental laws have to go through a special progress. For example, the US constitution has a special procedure for the amendment of the constitution.

For a statute law to be passed in the UK it has to go through both houses of Parliament and receive royal assent. The only exception to this is if the Parliament Act is invoked. This is a mechanism that allows the House of Commons to bypass the House of Lords if the Lords block a bill for two consecutive parliamentary sessions. Since 1949 the Parliament Act has only been used four times.

In both the House of Commons and House of Lords a Bill goes through the same legislative stages:

First Reading – The bill is outlined, usually without debate and a date is set for its Second Reading.
Second Reading – The bill is outlined and sometimes debated.
Committee Stage – A Public Bill Committee considers the bill and suggests amendments.
Report Stage – The House considers the report of the Public Bill Committee and debates and votes on amendments.
Third Reading – The bill is debated and a vote is held on the bill.

When the bill is agreed by both houses it is given Royal Assent by the monarch. This final stage, unlike a Presidential Veto in the United States, is a formality. The last time a monarch refused to give Royal Assent to a bill was in 1707 when Queen Anne refused her assent to a bill to form a Scottish Militia. She was advised by her ministers that the militia might be disloyal and so withheld her consent. If the monarch were to refuse to give Royal Assent to a properly passed bill today it would lead to a constitutional crisis that would almost certainly see the downfall of the monarchy.

Can a Statute Law be overturned in the UK?

An important constitutional principle in the UK is parliamentary sovereignty. This principle was codified by the Victorian scholar AV Dicey into three key parts:

1. Parliament can make laws concerning any matter

2. No Parliament can bind its successor

3.  A valid Act of Parliament cannot be overturned by any other body 

This means that a statute law can only be repealed (overturned) via a decision of Parliament. Indeed, if a statute law is passed that conflicts with another law, the Doctrine of Implied Repeal comes into play and the later law automatically repeals the previous one.

This principle differs to the constitutional principle that exists in the US. The United States has constitutional sovereignty. This means that ultimate power derives from the constitution itself. In the United States a congressional or state law can be struck down (overturned) by the courts if it is found to be unconstitutional. Indeed, since 1920 there are 670 state or federal laws that have been overturned by the Supreme Court.

In the UK there is no mechanism for a Statute Law to be overturned by any body outside of Parliament. The courts may make recommendations about a bill, for example stating that they do not think it complies with the Human Rights Act (1998), however, it is down to Parliament alone as to whether to amend the legislation in question.

There are mechanisms through which laws in the UK can be scrutinised by bodies outside of Parliament:

Human Rights Act (1998) – In 1998 Britain passed the Human Rights Act. This codified the European Convention of Human Rights into British law. The act states that all laws passed in Britain must comply with the provisions of Human Rights Act. If a case is bought to court judges can issue a ‘declaration of incompatibility’ if they feel a law is not inline with the Human Rights Act. However, it is up to Parliament to decide whether or not to change the legislation – judges cannot force them to do so.

European Court of Human Rights – Since 1953 Britain has been a signatory of the of European Convention of Human Rights and under the jurisdiction of the European Court of Human Rights (EctHR). The EctHR can highlight when a member state is not complying with the convention. However, it is up to member states how they react to this. Famously, the Government of David Cameron refused to accede to the EctHR judgement that prisoners should not be automatically banned from voting.

European Court of Justice – When Britain was a member of the European Union it accepted that EU Law took precedence over UK Law. The ECJ could challenge British law when it believed it conflicted with EU Law. Again, it would be up to the British Parliament whether to change the law that was in confliction.

In summation, whilst there are a number of institutions that may be able to question British law, there is no institution that can force Parliament to amend it.

What is Common Law and what is its relationship with Statute Law?

Common Law is often referred to as ‘judge made law’. Common Law is precedential and some of it predates Parliament itself. When judges make a decision it becomes part of the canon of law and it will then be considered in future by other judges. Statute Law, despite its importance, relies heavily on Common Law to ‘fill the gaps’. It is impossible for Parliament to consider all eventualities and implications when creating a new law – it is therefore left to judges to create common law through their judgements. For example, the Equality Act (2010) places a requirement on employers and public bodies to make ‘reasonable adjustments’ for a person with disabilities. However, what is ‘reasonable’ is subjective and dependent on situation. As a result, courts (in particular Employment Tribunals) have built upon case law to address what adjustments may or may not be reasonable.

Sometimes, however, common law can become unwieldy and statute law is required to tidy it up. A good example of this is he issue of Same-Sex Marriage. For a number of years judges had considered cases where same-sex couples wished to have the right to marry. The most famous case was Wilkinson vs. Kitzinger in 2006 where judges ruled that a same-sex couple had the right to a civil partnership, but not a marriage. This was clearly an issue which society wanted to see a change and so, in 2013, Parliament stepped in to create the Marriage (Same-Sex Couples) Act.

What constitutional reforms have been made via Statute Law?

Almost all major constitutional reforms have been made via statute law. When the Constitution is amended in the UK it is primarily done via Statute Law. Prominent examples of this are the Human Rights Act (1998) and the devolution acts of 1998. Increasingly, other sources of the UK Constitution are also being codified into Statute Law. For example:

Sewell Convention – The Sewell Convention that says that Westminster will not legislate on devolved issues was codified into law in the Scotland Act (2016) and the Wales Act (2017).

Posonby Rule – The Posonby Rule was a convention that stipulated that any international treaty should be laid before Parliament at least 21 days before ratification. The Constitutional Reform and Governance Act (2010) put this requirement into Statute Law.

Fixed-Term Parliament Act (2011) – Between 2011 and 2022 the Fixed-Term Parliament Act codified the way in which early general elections could be called. However, the Dissolution and Calling of Parliament Act (2022) returned the power to the Prime Minister through the royal prerogative.

Why does Parliamentary Sovereignty ensure statute law is always the supreme source of the UK constitution?

Parliamentary sovereignty ensures that the will of Parliament is always supreme to the will of any other body or institution. This means that Parliament can react quickly to any challenges to its authority. For example, in Ahmed V Treasury (2009) the Supreme Court adjudged that the Government had acted ultra vires by freezing the assets of suspected terror suspects. However, in response, Parliament quickly passed the Terrorist Asset-Freezing (Temporary Provisions) Act 2010 to make legal the very thing that the Supreme Court had ruled against. This shows the ability of Parliament to overturn any adverse verdict by another body.

In addition, whilst Parliament does not usually have any ability to scrutinise the royal prerogative powers of the Prime Minister, if Parliament passed a Statute Law they could remove that power from the Prime Minister.

It is clear, therefore, that Statute Law is superior to all other sources of the constitution.

Article Summary

Despite being one of many sources, Statute Law is the most important source of the UK Constitution. To summarise, the reasons for this are:

• Statute Law is the mechanism via which major constitutional reforms are made.
• As a result of Parliamentary Sovereignty, there is no mechanism via which a Statute Law can be overturned other than its repeal by Parliament.
• Statute Law is used to clear up inconsistencies or areas of unclarity in Common Law.

Key Terms

Statute Law – Laws created via Act of Parliament. They are considered the superior form of law.

Primary Legislation – Legislation passed via a full Act of Parliament.

Secondary Legislation – Legislation delegated by Parliament to another person or institution.

Statutory Instruments – Sometimes also called ‘secondary legislation’. These are laws that can be passed by the executive having been pre-authorised by another Statute.

Parliamentary Sovereignty – A central principle of the UK constitution under which nobody can overrule parliament and parliament can ‘make and unmake any law’.

Constitutional Sovereignty – A political system where a Codified Constitution is where all power flows from. This is the case in the U.S.A.

Parliament Acts – Acts of Parliament in 1911 and 1949 that blocked the ability of the Lords to block legislation and then reduced its delaying power.

Royal Assent – The final stage of the legislative process in which the Monarch agrees to a law. By convention Royal Assent is now never refused, the last time it was refused was by Queen Anne in 1707.

Human Rights Act (1998) – The UK Act of Parliament that placed the ECHR into British law.

European Convention of Human Rights – An international treaty to protect and enforce fundamental Human Rights in Europe. It was signed in 1950. In 1998 it was codified into UK Law in the Human Rights Act.

European Court of Human Rights – The Court based in Strasbourg which is responsible for ensuring that the European Convention of Human Rights is carried out in countries that have signed up to it.

European Court of Justice – The court of the European Union in Luxembourg. It is responsible for overseeing cases whereby Member States have questioned, or have not followed, European Union directives and regulations.

Ultra Vires – A finding that the government or a government body has acted beyond its power or authority.

Common Law – This law is made by taking into account the previous conclusions of judges. This creates a judicial precedent for judges to use in the future. This is often referred to as judge made law. Importantly, it ‘fills the gaps’ left by Statute Law.