Developed in the 18th century by the French philosopher, Montesquieu , the doctrine of the separation of powers has been a controversial issue in British constitutional law. Whilst it is evident there are three individual branches of power, it is not wholly clear if the functions of these branches are kept concretely independent from one another. Certainly prior to the Constitutional Reform Act 2005, (herein referred to as the Reform Act), there was much overlap between the judiciary, and both the executive and legislative. The changes made by the Reform Act were indeed successful in creating a greater separation of powers, through the change of positions such as Lord Chancellor and the Law Lords. Furthermore, the Act was the first time the role of the judiciary was made entirely independent of government and enshrined in statute. However, the UK still does not have a strict separation of powers. The judiciary is not wholly independent of both the legislative and the executive. Whilst the Reform Act did strengthen the separation of powers in the UK from its previously weak position, the doctrine is not categorical.

Prior to the Reform Act, there was arguably significant overlap in the branches of power, but particularly with the judiciary. The position of Lord Chancellor was one which was incompatible with the independence of the judiciary, and therefore the doctrine. It was said by legal commentators that; “The Lord Chancellor’s position…compromised the judiciary…as an independent body.”
The Lord Chancellor effectively participated in all three branches. He made legislation, executed the legislation and furthermore, he could adjudicate on legislation he had helped create. This was problematic, as it infringed upon the right to a fair trial under Article 6(1) , an issue which was highlighted in the case of McGonnell v UK. Whilst there was a theoretical