In the UK, voters elect a Member of Parliament who is there to represent the views of their constituents. This is representative democracy, and the UK has survived pretty well with this form of government. It is one of the many things that the Romans Have Done For Us.
Members of Parliament are supposed to do what their constituents tell them to do. They may have loyalty to the political party to which they belong, but they should, at least in theory, represent the views of their constituents.
The recent referendum on whether the UK remains a part of, or leaves, the European Union, has caused a great deal of uncertainty, and it is clear, when you think of it, why this is so.
Consider the stylized map of the UK below, where the country is split into three constituencies. Each constituency has 1 million electors, who all vote.
Constituency A votes 800,000 Leave : 200,000 Remain;
Constituency B votes 400,000 Leave : 600,000 Remain; and
Constituency C votes 400,000 Leave : 600,000 Remain.
This means that there is a total of 800,000 + 400,000 + 400,000 = 1,600,000 voting for Leave; and 200,000 + 600,000 + 600,000 = 1,400,000 voting for Remain.
This is democratic. The will of the people is that, by a sizeable majority, Leave wins.
However, when this is ratified in Parliament*, by the representatives of the people, the consituents’ MPs, the following happens:
The MP for Consituency A votes Leave;
The MP for Consitutency B votes Remain;
The MP for Consituency C votes Remain.
We are then left in the paradoxical position that a referendum result‡ cannot – under a representative democracy system – be implemented by the MPs.
This is a key constitutional question, and one that cannot be solved by Parliament or the Judiciary†. This is a fundamental issue for British (and European) democracy. And its importance cannot be overstated.
* there is a fierce debate on which body needs to invoke Article 50(2) of the Treaty of European Union, but let us assume that Parliament would make this decision ‘in accordance with its own constitutional requirements’ under Article 50(1).
† it is clear that the decision will be the subject of Judicial review, right up to the Supreme court, but this will merely be a judicial rather than a democratic decision.
‡ this is not quite the situation in the actual Brexit referendum result (although there is no way of telling, as MPs’ constituencies are different from referendum counting districts), but the fact remains that the result of a referendum can be inconsistent with implementation under representative democracy.
Update 3 November 2016: The High Court (subject to appeal to the Supreme Court) has confirmed that Parliament should decide how to implement withdrawal, as the powers of Royal Prerogative would have an impact on Statute, which is not normally the case when treaties are made or revoked. Brexit is a special case, as it would overturn Statute in a way that was not envisaged in the European Communities Act 1972. The full judgment is here).