In its White Paper the Scottish Government argued convincingly that an independent Scotland would remain a member of the EU after the legal route that is available under Article 48 of the Treaty of the EU.

Both Graham Avery, veteran EU negotiator and European Commission Honorary Director General, and Sir David Edward QC, former British judge at the European Court of Justice, support the plausibility of this route. It would be the UK Government's obligation to table a proposal for the amendment of treaties under Article 48 to take account of the fact Scotland had voted to become independent.

The other EU countries would require to agree to the amendment which effectively would mean that Scotland would continue to be a member state. They would be likely to do so for practical reasons. Scotland is EU's largest oil-producing nation, also boasting 25% of Europe's renewable energy potential. The Spanish fishing fleet, among others, fish extensively in Scottish waters. Is it really likely that the other member states of the EU would want to be deprived of the benefit of Scotland's oil, renewable energy potential and fishing stocks?

Lawyers for Yes consider there is a second powerful legal argument for Scotland's continuing EU membership after a Yes vote. This argument is based on the right of people living in Scotland to continuing EU citizenship. It also received support from Sir David in his evidence to Holyrood.

The argument runs as follows; Scotland is part of a member state and has been for more than 40 years. Accordingly, all the citizens of Scotland enjoy the benefits of EU citizenship. It would not be acceptable in terms of the EU treaties for Scotland's citizens to be stripped of EU citizenship and all rights that go with that status simply because they had exercised their right to self-determination in a legally constituted referendum. An expert on European Law, Aidan O'Neill QC, although not one of our number at Lawyers for Yes, has written: "The fact of continuing EU citizenship of the formerly British national residents of an independent Scotland seems to me to be a trump card in any negotiation for the territory of Scotland remaining within the EU, albeit now represented as a distinct Member State by an independent Scottish Government."

Two recent decisions of the Grand Chamber of the European Court of Justice lend support to this argument by asserting the importance of the status conferred on nationals of member states by the Union rules of citizenship. In C-135/08 Janko Rottmann v Freistaat Bayern, judgment of March 2, 2010 it was held that an Austrian man who had moved to Germany to avoid criminal prosecution could not have his German naturalisation cancelled if that would leave him stateless and deprive him of EU citizenship. In Case 34/09 Ruiz Zambrano v Belgium, judgment of March 8, 2011, the court held that Colombian parents of children born in Belgium and who were Belgian citizens could not be deprived of their right to remain in Belgium given their status as parents of EU citizens.

The Court concluded that national measures cannot deprive EU citizens of the "genuine enjoyment of the substance of the rights conferred by virtue of their status as citizens of the union". Lawyers for Yes therefore believe that, according to law, Scottish citizens cannot have their European citizenship suddenly withdrawn. We also believe that, no matter how long the negotiations take for Scotland to become a full member state, Scotland will not find itself outside the EU.

If there is a Yes Vote, it follows, both as a matter of law and realpolitik, that Scotland will not be taken out of Europe against the wishes of her people. By contrast, in the event of a No vote, there is a very real possibility this will happen if David Cameron has a mandate to hold an in-out referendum. Such an eventuality seems increasingly likely after Ukip's first place in the European elections in England and the UK Government's histrionics over Jean-Claude Juncker's appointment as President of the European Commission.