Parliament supremacy means that a legislative body is supreme to all other government institutions, including any executive or judicial bodies. Generally, the courts cannot overrule its legislation and no Parliament can pass laws that future Parliaments cannot change. It is very much evidenced that parliament is supreme in the UK, the only question is, is it losing its supremacy, if so to what extent?
Parliamentary sovereignty is the most important part of the UK constitution, it has been for a very long time. The UK is known to have an unwritten constitution, however, although, they do not exist in a single text, like other countries e.g. USA and Germany, large parts of the UK constitution is actually written down, most of it being statutes. “Therefore, the UK constitution is often described as ‘partly written and wholly unmodified'”.
The doctrine of parliamentary sovereignty is about the relationship between the Parliament and the courts. Is parliament supreme or the courts? As we have stated above, UK is known to have parliament supremacy, but to what extent? Dicey puts forward that parliament is supreme, meaning that ‘Parliament has, under the English constitution, the right to make or unmake any law whatever; and further that no person or body is recognised by the law of England as having a right to override or set aside the legislation of Parliament'.
The doctrine of parliament sovereignty of the United Kingdom has been regarded as the most fundamental element of the British constitution. It can be summarised in three points; parliament has the power to make any law they wish, and no parliament can create a law that a future parliament cannot change and only parliament can change or reverse a law passed by parliament. It gives unconditional power to the Westminster Parliament. A.V. Dicey describes it as ‘the dominant characteristic of our political institutions', ‘the very keystone of the law of constitution'.
Consequently, it is said that the courts have no authority to judge statutes invalid, and that there are no fundamental constitutional laws that parliament cannot change, other than the doctrine of parliament sovereignty itself.
Therefore, the only instance when courts are willing to question the legitimacy of statutes is when there is a question as to them not being passed using the correct procedure; which is passing through both Houses and receiving the Royal Assent. This is known as the 'Enrolled Bill' rule. This is demonstrated in the case of Edinburgh & Dalkeith Railway Co. v Wauchope (1842) 8 Cl & F 710, where Lord Campbell pronounced:
'...all that a court of justice can do is to look at the Parliamentary roll: if from that it should appear that a bill has passed both houses and received the Royal Assent, no court of justice can inquire into the mode in which it was introduced into Parliament, what was done to it previously being introduced, or what passed in Parliament during the various stages of its progress through both houses of Parliament.'
These views were again supported in the cases of Ex Parte Canon Selwyn (1872) J.P. 54 and Pickin v British Railways Board  AC 763. Both the Parliament Act 1911 and 1949 and The Regency Act 1937 and 1953 changed the Enrolled Bill Rule.
In order to keep away any conflict both the parliament and the courts have been carefully avoiding any acts to cause so. A statement by Lord Reid shows, again, the courts unwillingness to question the validity of an Act:
“For a century or more both Parliament and the courts have been careful not to act so as to cause conflict between them. Any such investigations as the respondent seeks could easily lead to such a conflict, and I would only support it if compelled by clear authority. But it appears to me that the whole trend of authority for over a century is clearly against permitting any such investigation.”
A statement by Megarry V-C, suggests that even if parliament had not done all it should to pass an act, the courts will still not get involved, and it would not be investigated as long as necessary assents have been given:
‘the duty of the court is to obey and apply every Act of Parliament, and the court cannot hold any such Act to be ultra vires.'
Ultra Vires meaning: “without authority. An act which is beyond the powers or authority of the person or organization which took it.”
When it comes to international law, the courts may still not question an act if it is contrary to it, which has been demonstrated in Cheyney v Conn  1 All ER 779. Here it was claimed that money from tax given under the Finance Act 1964 would be used in a way contrary to international law. A similar case was that of R v Jordan  Crim L.R. 483 Again this failed as the judges were unwilling to question the validity of the Act. .
Another case is that of Manuel v AG  3 All ER 786,822, which I have given a statement form, as above. “Here Canadian Indian chiefs tried to declare the Canada Act 1982 invalid. They argued that although it claimed to have consulted the people of Canada it had not consulted them and therefore should not have been passed. The Court of Appeal held that there was nothing they could do once the Act was passed, it was too late.”
As a result, theoretically, we can say that Dicey's doctrine of parliamentary supremacy is true, however, practically, we may not be able to say the same thing.
There has not been much doubt about the doctrine just until recently, it was almost unthinkable that the courts would ever refuse to apply an act of parliament.
In Britain, many senior judges and academic lawyers have challenged the theory, the master of the Rolls, Lord Woolf of Barnes, has asserted that there are 'limits on the supremacy of parliament witch it is the courts inalienable responsibility to identify and uphold. But he has subsequently stated that the ‘courts accept the sovereignty of parliament' and that ‘the vast majority if not possibly all the senior judiciary' - himself included - think it undesirable for the judiciary to be given power to invalidate statutes.
Sir John Laws has argued that true sovereignty belongs not to parliament, but to the unwritten constitution, which includes fundamental principles, such as democracy and freedom of expression, that the judiciary can enforce if necessary, by invalidating statutes.
Without going that far, Sir Stephen Sedley has suggested that the doctrine of parliament sovereignty has been replaced by ‘a new and still emerging constitutional paradigm', consisting of ‘a bi-polar sovereignty of the Crown in parliament and the Crown in the courts'.
However, we can still determine, even though subject to much criticism today of parliamentary supremacy, it is still seen that parliament is supreme. Though there are factors that affect the supremacy of parliament, those factors have still been undertaken, with the discretion of the parliament. The parliament accepted to give up a little of its powers and can take it back any time, to keep all of its supremacy.
Another fact to consider is the effects of the European Union, the Human Rights Act 1998, Devolution of power to Scottish Parliament and Welsh Assembly and the establishment of the UK Supreme Court. “These factors do not fundamentally undermine the principle of parliament supremacy, at least in theory, as parliament could repeal any of the laws implementing these changes.”
The Scottish Parliament and Northern Ireland Assembly are both able to pass primary legislation within the areas that have been devolved to them. As the system remains devolved and not federal, the powers of these assemblies stems from the UK Parliament and can be suspended, as has happened with the Northern Irish case. However, this seems unlikely to happen in Scotland or Wales, as such a decision would (currently) be highly unpopular with the electorate in both places.
“Secondly, the institutions of the European Union, in particular the European Court of Justice (ECJ) which asserts the power to exercise judicial review over UK law. In this situation, an adverse finding by the ECJ that a UK law is inconsistent with the EC Treaties automatically annuls the law, since the European Communities Act 1972 ("ECA") provides that European Community law is supreme in the United Kingdom. The first example of this in relation to a statute, the Merchant Shipping Act 1988, was the Factortame case. The ECA has been thought of as a 'constitutional statute'. In the case of Thoburn v Sunderland City Council the Weights and Measures Act 1985 was held not to implicitly repeal the ECA. This has been argued to compromise the effect of parliamentary sovereignty, as the ECA must be expressly repealed in order to be negated by subsequent incompatible legislation.”
Thirdly, the European Convention on Human Rights and the incorporation by the Human Rights Act 1998 of the European Convention a finding of a breach of Convention rights by the ECHR does not automatically annul the law: in practice, the Government is bound to implement the ECHR's decisions. The Human Rights Act includes a mechanism under which British courts can declare an Act of Parliament to be in violation of the Convention by making a declaration of incompatibility. This power, like that of the ECHR, does not automatically annul the law. Where a declaration of incompatibility has been made, the Government is able to use an accelerated procedure to enact a bill to repeal the offending law. However, the UK Parliament could still vote to withdraw from the convention, as has been suggested by some British newspapers, and backbench Conservative MPs.
In conclusion, There is a concept in political science of 'legal' and 'political' sovereignty. It can be argued that legal sovereignty has not been lost, because Parliament still retains all its theoretical powers. There are no legal limits on Parliament's sovereignty. However, as it is highly unlikely that the UK would repeal the European Communities Act and leave the EU, and it is unlikely the devolved legislature would be abolished, there are significant political limits on the sovereignty of Parliament. Nevertheless, it remains the case that the UK Parliament could do so without seeking the mutual consent of the EU or the devolved legislatures, as it did with the abolition of the Parliament of Northern Ireland in 1972, and that if it did, these repeals would be legally and politically binding.
Alder., 2009. Constitutional and Administrative Law. Palgrave Macmillan
Bradley - The Sovereignty of Parliament - in Perpetuity?
Cheyney v Conn  1 All ER 779
Dicey, A.V., 2010. The Law of Constitution. Liberty Fund Inc.
Edinburgh & Dalkeith Railway v. Wauchope (1842) 8 Cl & F 710- HL
Ex Parte Canon Selwyn (1872) J.P. 54
Manuel v Attorney General  Ch 77, 86
Parliamentary Sovereignty, Contemporary Debates, Jeffrey Goldsworthy, Published July 2010
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Pickin v. British Railways Board  AC 765 - HL
R v Jordan  Crim L.R. 483
Turpin, C., & Tomkins, A.,2007. British government and the constitution: text and materials. Edition 6. Cambridge University Press
Wade, E.C.S., & Bradley, A.W., 1985. Constitutional and Administrative Law. 10th ed. Longman
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