By the time you read this, the UK will have made its decision, but I am writing the day before the vote. However, looking at how the UK might leave the EU has been instructive for everyone, whatever the result.

If a member state votes to leave the EU, what happens next looks obvious, but only at first sight. Article 50 is the Lisbon Treaty provision for a process to leave the EU, and the UK Prime Minister indicated that he would invoke it without delay. So why did the official Leave campaign – Michael Gove, and others like myself – suggest this is not what should be done? After all, it provides that the EU shall “negotiate and conclude an agreement with that State, setting out the arrangements for its withdrawal, taking account of the framework for its future relationship with the Union.” What more would a seceding state want?

Unfortunately, there is more to the Article 50 process than just that. It is unacceptable, because it ties up the seceding state in EU knots, binding it into a process as a subservient member of the EU. They would have to negotiate as a supplicant, rather than as the sovereign state, just endorsed by voters in a referendum.

There are three critical elements of Article 50, beyond the soft words quoted above. First, the other 27 heads of government can conclude the agreement by qualified majority. The departing state is excluded from that decision. Secondly, the European Parliament must approve the agreement, so that at the end of the process, whatever agreement has been reached by the democratically elected heads of government could be overruled. Third, and most significantly, it stipulates a two-year period. This is the most serious problem. For at least two years (and it can be extended by consensus), the departing state would remain absolutely bound by all the obligations of EU membership, even though the voters had agreed to take back control over their laws, national constitution and their money. And the agreement reached by the 27 can effectively be imposed, unless at that last stage, the leaving state overthrows the whole process (and that really would create bad blood).

There is no need to invoke Article 50 straight away, if at all. It was only included in the Lisbon Treaty to make leaving the EU more difficult. In our campaign, it was advocated most hotly only by those who would rather the UK remained in the EU come what may: those around the Prime Minister, the Foreign Office, the other member state governments and EU Commission.

Before Lisbon, there was always a means of leaving the EU. In 1975, Harold Wilson instructed the then Cabinet Secretary to be ready to prepare legislation immediately for the repeal of the 1972 European Communities Act, to rescind the obligations of membership and to absolve the country of the requirement to implement EU law. There was no question of it taking years to restore the power of our Parliament. Today’s Cabinet Secretary should have been so instructed again. Whatever negotiations are necessary should only take place with that legislation on the statute book, ready to come into force at the right moment, and without any agreement if necessary.

If there has been a leave vote in the UK, many lawyers and civil servants will be insisting that the UK has an obligation to respect Article 50. They can argue that it is at least an obligation under international law. According to the Vienna Convention on Treaties, where a mechanism in the Treaty exists to abrogate that treaty, then that procedure should be followed. And while we remain a member of the EU, it is also an obligation that applies in our own law. This is precisely why interpreting a vote to leave the EU in this way is so dangerous.

In fact, in practical and constitutional terms, the departing state would be under no such obligation. No international court is going to insist that a government must submit their country to a process laid down in a treaty their voters have just rejected in a referendum.

When a state votes to leave the EU in a referendum, the sensible thing would be to accept the result, to commit to pause and to reflect, and to bring forward proposals for discussion and consultation for implementation under that state’s own constitutional arrangements. The only concrete commitment the UK government must make if the UK votes to leave the EU is that the UK will indeed leave the EU, and that the necessary legislation to repeal the European Communities Act will be brought forward as swiftly as possible.