Parliamentary Sovereignty And Rule Of Law
The United Kingdom (UK) constitution, being an unwritten one, relies on its Parliamentary sovereignty and rule of law to retain its authority in governing its four counterparts, namely England, Wales, Scotland and Northern Ireland. A constitution would provide for the establishment of various institutions of the State, regulation of relations between each institution and relations between the institutions and the citizens. The doctrine of separation of power is then introduced to regulate the constitution for more efficient check and balance of the governing minority. Aforementioned concept is particularly unique in the unwritten nature of the UK constitution as powers of each institution, the Executive, Legislature and Judiciary, are not codified nor listed on a tangible code of document that separation of power is diluted with a series of shared powers between each institution. Bound by conventions and ministerial responsibilities, coupled with recent reforms done to the UK constitution, occurrence of events involving an institution empowering over another is minimal albeit not having strict separation of powers.
Historical development of separation of powers
Historically, English separation of powers was actually done between the Crown and the Parliament. As early as the thirteenth century, Magna Carta 1215 was signed, promising the liberties of English freeman. This would limit the powers of the Crown which had been growing exponentially since the Norman conquest of 1066. At that point, no Parliament was formed yet. It was only during the middle of the fourteenth century when a “bicameral Parliament"  was established.
During the fourteenth and fifteenth century, a few principles were laid out based on the Magna Carta which formed the “ancient constitution  " to check the Crown’s power. These principles included the issues of taxation and passing of legislation with Parliament’s consent and the rights of the Commons to look into the Crown’s administration  .
Subsequently, after the break out of the English civil war in the 1640s and the overthrown of James II, a Catholic, the throne was offered to William and Mary by the Parliament through the Bill Of Rights 1689. The rights stated in the Bill of Rights are, in fact, the rights enjoyed by the Parliament. The Act of Settlement 1700 which clarified the line of succession to the throne further stressed on the sovereignty of the Parliament.
Separation of powers: Strict VS Weak
In the eighteenth century though, the view of separation of power is very much different from the historical view of the English separation of power. As interpreted by Montesquieu, separation of power is “when the legislative and executive powers are united in… the same body of magistrates, there can be no liberty...  " Such concept has framed the basic American constitution and is illustrated as a distinct delegation of work among the three main branches of the government, namely the executive, legislature and the judiciary. The executive would implement policies and administrate the country; the legislature makes laws and scrutinizes the executive’s work; the judiciary to apply laws as laid down by the Parliament as well as adjudicating matters.
According to Bradley and Ewing  , an ideal way of governing the country in line with the doctrine of separation of powers is that the composition of each organ of government should be different. There should be no control or interfere of functions of an organ of government over the other. The function of one organ should not be overlapping over another too.
In the United States (US), strict separation of power is noted from the creation of three branches of Constitution, headed by the President  , the House of Congress  and the Supreme Court  respectively. These branches are forced to be accountable among each other to prevent usurpation of power over another.
On a contemporary note, unlike the US where such constitution is by design rather than accident, the three organs of the United Kingdom were set up at different times in response to different needs. A series of overlapping of functions and institutions of the government is especially crucial in an unwritten constitution like the United Kingdom’s where its sovereignty lies in its Parliament to perform check and balance.
UK’s weak separation of power shall thus be further explored in three categories: executive and legislature, executive and judiciary; legislature and judiciary.
Executive and Legislature
Since the early eighteenth century, the Executives, represented by Government of the day and civil servants, are Crown servants and are accountable to the Parliament. Presently, the overlapping functions of the Executive and the Parliament reflect the ‘Westminster model’ of parliamentary government in the UK. As Walter Bagehot, a great 19th century constitutional essayist described it, “The efficient secret of the English Constitution may be described as the the near complete fusion; of the executive and legislative powers." 
Therefore, unlike in the US where the President is elected separately from the representatives of the House of Congress, members of the Executive in the UK must come from either House of Commons or House of Lords. The majority of seats governmental ministers have in the Parliament, according to Lord Hailsham, are a form of ‘elective dictatorship  ’. The Executive exercises royal prerogative in the name of the Crown so ultimately, it is often an issue as to the extent of influence the Executive has on the Parliament.
Furthermore, the Executives, including civil servants who run the administration of the state, are given the task of delegated legislation which is to fill in more complex details of the parent act passed by the Parliament. Such delegated legislation usually includes statutory instruments and Rules or Codes of Practice.  The Executives are given such delegated law making powers to share the workload of the Parliament because in constructing a thorough Act of Parliament, more Parliamentary time would be required for finer details, which the Parliament would not have as much knowledge compared to the Executives anyway.
On another note, with Parliamentary sovereignty, only successful governments are those with strong parliamentary support. Theoretically, the Parliament has the right to make the Government of the day to resign when it can no longer command a majority with votes of no confidence  in the House of Commons. The most recent example was the resignation of the Callaghan Government on 28 March 1979 which resulted in the victory of the Conservative Party led by Margaret Thatcher. Opposition leader, David Cameron had called for a fresh election too in light of the MPs scandal  in 2009 but with the concern of no alternative leader, list of votes of no confidence were not published  .
Apart from that, departmental select committees (DSC) are set up for more systematic scrutiny Executive’s activities by Parliament. Expenditure, administration and policy of principal government departments are examined by said committees  by making sure civil servants disclose accurate information during Question Time. The liaison committee, made up of Chairmen of DSC, would also raise Question time which the Prime Minister would have to be available for twice a year. A shadow cabinet is set up too to watch over the workings of the original ministers.
Despite the overlapping in composition and functions, clearer separation of powers between Executive and Parliament can be noted in the House of Commons (HOC) Disqualification Act 1975  . Section 1(1)(b) of this act provided that civil servants, armed forces and police force which are part of the Executives are disqualified from the membership of the House of Commons. Section 2 has also stated that not more than 95 holders of Ministerial offices are allowed to sit and vote in the House of Commons. With consideration given to Parliamentary Private Secretaries (PPS) though, the government generally enjoys the support of 120 MPs. This is because 3.8 of the Ministerial Code states that “PPS are expected to support the Government in important divisions in the House. No PPS who votes against the Government can retain his or her position  ."
Ultimately, as far as creating a clearer identity between Executive and Parliament, achieving the balance between royal prerogative and Parliamentary sovereignty is what really matters for the English constitution to work.
Executive and Judiciary
Royal prerogative, according to Dicey, is ‘the residue of discretionary or arbitrary authority… legally left in the hands of the Crown  ’. As opposed to the superiority of Executive’s prerogative powers, such powers must be found upon legal and lawful authority. Quoting Lord Coke in the Case of Proclamations 1611  , the king ‘hath no prerogative but that which the law of the land allows him’. Therefore, in order to uphold the rule of law, this is where the Judiciary steps in to perform check and balance on the Executive.
Over the years, judges have been asked to preside over royal commissions, departmental committees and inquiries where political issues are abound. This has greatly exposed judges as tools used by the Executives for deciding on controversial issues as to not affect its strong command of majority in the Commons. A few examples of this would be the Arms for Iraq affair, the Profumo affair and the Hutton Inquiry. The judges would also be criticized by the losing side of a political inquiry in producing a whitewash report, resulting in further disputes.
On the other hand, the Executive’s encroachment into the function of judiciary can also be related in Easterbrook v United Kingdom (2003)  where after certifying that discretionary life provisions should apply to Easterbrook, the Secretary of State further reviewed Easterbrook’s tariff and reduced it to 12.5 years following the recommendation of the Lord Chief Justice  . Fixation of such tariff should have been determined by the judges, rather than a party politician and a member of the Executive. This can be paralleled with the Malaysian judicial crisis  in 1988 when the Prime Minister had tabled a Bill to divest the courts of the “judicial power of the Federation", as granted by Parliament, and empowering the Attorney-General to determine venues for cases. This had eventually led to the blatant suspension of then Lord President, Tun Salleh Abas as well as two Supreme Court judges, Tan Sri Wan Suleiman Pawan Teh and Datuk George Seah  for ‘misconduct’.
The rule of law states that the government is as much subjected to the laws as the governed. Hence, in spite of all that, it is crucial to note that the main responsibility of the Judiciary is to bring the Executive exercise of discretionary powers within the scope of judicial review  . By distinguishing the ‘Crown as monarch  ’ and the ‘Crown as government  ’, carrying out judicial review of Executives who have acted ultra vires is a much easier task. The Crown Proceedings Act 1947  might preserve the Crown’s immunity from injunction, but not for the officers of the Crown like in the case of M v Home Office (1994)  . Mr. Kenneth Baker, the then Home Secretary, had been held guilty of contempt of court, for failing to abide by orders from the court for the non- deportation of M, a Zairian teacher claiming refugee status. This can be contrasted with Council of Civil Service Unions v Minister for the Civil Service (1985)  , the “GCHQ case", in which the Minister for the Civil Service, by using her prerogative, instructed that staff of the Government Communications Headquarters (GCHQ) can no longer join national trade unions as they hold secrets in which national security is involved. The court has decided that royal prerogative exercised by the Executive is reviewable by courts but such judicial review only limits to justiciable matters. Non- justiciable matters, on the other hand, concern with national security, high policy and declaration of war. It is said that these non- reviewable matters are ‘best left in the hands of the Executive’ in line of with the doctrine of separation of powers.
Thus, as the Judiciary’s function is adjudicating matters, not only among the public but also between other organs of government, it would be more appropriate for the Judiciary to be a neutral and independent body to uphold the rule of law. Sufficient separation of power should be made clear here in prevention of judges dragging themselves into political disputes.
Legislature and Judiciary
Historically, the law of the land was developed through common law cases. It was only in the nineteenth century when Parliament became the principal law maker  . Since then, Judiciary is subordinate to the Parliament, applying laws as laid by the Parliament due to Parliamentary sovereignty.
Despite that, it is rather questionable as to whether judges make the law through statutory interpretation. In the judges’ defence, instead of giving available statutes new meaning, it is more of translating the wishes of the Parliament through interpreting it as accurately as possible. In addition, in the case of Magor and St. Mellons Rural District Council v Newport Corporation (1950)  , Lord Denning had mentioned that when there’s a lacuna in the legislature, it is the judges’ function to fill in such gap. This is, however, critcised by Lord Simonds, claiming that this would result in a ‘naked usurpation of the legislative function under the guise of interpretation  ’.
Furthermore, Parliamentary sovereignty is challenged through the introduction of the European Communities Act (ECA) 1972  . It is said that European Community (EC) law prevails over national law and S2 (4) of the act ensures the courts interpret law according to the requirements of Community law. Rather than ordinary statutory interpretations, it is more appropriate to term that as constitutional interpretations. The Human Rights Act (HRA) 1998  put a serious dent on Parliamentary sovereignty too when declaration of incompatibility  can be made by judges when an Act of Parliament opposes the Community law. Arguments can be made as to the legal rights of Parliament in amending both HRA 1998 and ECA 1972 should the need arises in the future.
It must also be reminded that the Parliament can always overturn a judicial decision as witnessed in the case of Burmah Oil Co Ltd v Lord Advocate (1965)  . The House of Lords (HOL) had ruled that the government would pay compensation due to damages done to properties belonging to oil companies during the Second World War. The War Damages Act 1965  with retrospective effect was then passed on immediately after by the Parliament, nullifying the judiciary decision made in the earlier case.
On the other hand, more notable separation of powers between the legislature and judiciary is observed in the HOC Disqualification Act 1975  Section 1(1)(a) where judicial offices holders are disqualified from the HOC. It is even more apparent after the Constitutional Reform Act (CRA) 2005  as before the act, the law lords, sitting in the HOL, look into the technical aspects of the law making process even though by convention, they do not involve in debates. It is absurd as the very same lords were the ones hearing appeal cases as the Highest Court of the Land and hence, leads to lack of objectivity in applying laws. As of 1 October 2009, the law lords had officially moved out of the HOL to an independent body known as the Supreme Court.
Besides, it is of Parliamentary Practice that debates concerning judges cannot be raised. Matters awaiting or under adjudication in all courts exercising a criminal jurisdiction are undebateable too  . It is only during Parliamentary Questions time when ministers are allowed to comment on individual judges  .
The office of Lord Chancellor
It is finally established that a less than clear separation of powers in the UK could prevent the occurrence of a constitutional deadlock. It must be noted, however, that all power cannot be fully vested in the hands of one person to prevent abuse and loss of liberty,  especially when the boundaries of said power is uncertain due to the unwritten nature of the constitution.
A violation of a strict separation of power lies in the office of the Lord Chancellor. The Lord Chancellor holds altogether three positions: Minister of Justice for the Executives, automatically the speaker of the House of Lords in the Parliament and lastly, Head of Judiciary. The Lord Chancellor is also in charge of the appointment and selection of senior judges. The absence of separation of powers here would thence encourage the Lord Chancellor to act ultra vires as there is no scrutinisation on the Executives.
Fortunately, with the CRA 2005, the Lord Chancellor is now only the Minister of Justice. The Judicial Appointments Commission (JAC) is also set up, with nine from the legal fraternity and six with non- legal background in selection of judges. Selections done by the JAC can only be rejected by the Lord Chancellor once. Separation of powers is clearly set out here so that abuse of power can be prevented.
It is understood that various changes had been made to ensure better clarity of the separation of power in UK over the years. Due to its unwritten constitution, the UK constitution is certainly unfit for a strict separation of power. In order to overcome that, by way of clearer illustrating the English separation of power, one can suggest for a partly written constitution for the UK by codifying certain conventions in relation to the separation of powers between the Executive, Legislature and the Judiciary; royal prerogative and Parliamentary sovereignty for instance. All three organs of the government need to work hand in hand to avoid constitutional deadlock and by doing so, boundaries can be created and confusion be avoided as to the occasionally dual functions of each constitutional institution.