Behind the politics of the Brexit dispute is a deep question about what constitutes the legitimate exercise of power.

Some laws, such as budgets, are passed on an annual basis, and are temporary in the duration. Other statutes are intended to last indefinitely. However, for the basic building blocks of a state, a different type of law is understood to exist: constitutional law.

The UShas one of the oldest written constitutions in the world. Its articles and amendments have provided fertile ground for political arguments for nearly two and a half centuries. Other countries have followed its example. Most had definitive events when their constitutions were created.

The UKis almost unique in the world, in that its constitution did not form after a singular event and is not codified in a single document. Much of it has never been written down at all but is embedded in norms and expectations established by history. It is not always clear where the powers in it came from, and on what basis they can now be used. Powers that are assumed to exist sometimes are just found to have evaporated.  It is said they have fallen into desuetude.  Other powers turn out to be much more significant than expected, particularly at a high time of crisis, as now.

This can raise issues about the legitimacy of government action. This is particularly profound when the executive clashes with the legislature as, unlike the US, the democratic and constitutional basis for these clashes cannot be referred to a basic law, which can be adjudicated by a supreme court. In our constitution, Parliament is sovereign, by which it is said that Parliament can make and unmake any law. Within the law, the government can carry out its functions and exercise its powers as it sees fit.

By the time this article is published, the outcome of the present clash about prorogation may well be settled. The government is trying to prevent Parliament from obstructing our departure from the European Union without a deal. Parliament is trying to obstruct such a departure, despite having passed the enabling legislation. Have no doubt! Parliament could remove the government if it wanted.  However, this House of Commons has demonstrated a tendency to wound the government, but a reluctance to kill it.

At the time of writing, the government has attempted to prorogue Parliament for a slightly longer period than normal – a few days. The means of this closure is by resort to Royal Prerogative, the powers which remain at the disposal of the Sovereign.  They are subject to the advice of ministers; which Parliament has never bothered to capture via statute law. Analogous powers are held by governments in all constitutions, written or unwritten.

The question that arises is not a constitutional one, but one of legitimacy. The legitimacy of many royal prerogative powers, such as ministers’ powers to advise the Sovereign to prorogue Parliament, have never been in doubt before now.  This time, however, the prorogation of Parliament reflects how the government is using this power to attempt to make life more difficult for those opposed to its agenda. Some say it is a “constitutional outrage.”  Those, like the Speaker of the House of Commons, tend to be against Brexit, and base their case on the supremacy of Parliament’s representative mandate.

We have an English saying: people in glass houses should not throw stones. The Speaker of the House of Commons has wide individual discretion over how the Commons operates, and has historically been trusted with such considerable power, on the basis that he would act in a neutral and impartial manner. However, this Speaker has used his power to interpret standing orders to change the meaning of what was intended when the standing orders were drafted, to help Brexit opponents in their parliamentary tactics. In doing so, he has set aside advice from the Clerk of the House. His latest statement professing “outrage” underlines that he has become a political participant as well as an adjudicator.

While the Speaker has the constitutional authority to act as he has, there are still questions about the legitimacy of his actions.

All Parliamentarians are subject to competing legitimacies.  The great Conservative philosopher Edmund Burke, in an address to his Bristol voters, made it clear,  “Your representative owes you, not his industry only, but his judgment; and he betrays, instead of serving you, if he sacrifices it to your opinion.”  Winston Churchill expanded on this when he intoned that “The first duty of a member of Parliament is to do what he thinks in his faithful and disinterested judgement is right and necessary for the honour and safety of Great Britain. His second duty is to his constituents, of whom he is the representative but not the delegate. It is only in the third place that his duty to party organisation or programme takes rank.”  However, neither Burke nor Churchill envisaged how referendums would become part of the UK’s constitution, and therein lies much of the confusion over Brexit.

Some in Parliament argue that it is MPs’ duty as representatives to seize back the EU question it decided to give to the voters to resolve. Boris Johnson’s government argues that it is an ambassador of the decision that the people have made to leave the EU, come what may.