sarah the question of EU membership is a very interesting one, and the answer seems to depend on who you ask! :-)
n international law, Scottish membership of the EU would depend on the question of which state or states are successor to the present UK. There are three answers to that question: (1)that the "rump UK" of England, Wales and Northern Ireland is the successor state, but a newly independent Scotland is not; (2)that both states are; or (3) that neither is.
(1)The balance of views among international lawyers supports the view that the rump UK but not an independent Scotland would be a member, but that is by no means universally held and many disagree. On the international law argument, the position is far from clear.
(2) if Scotland were to cease to be part of the EU and had to apply for membership, that would involve stripping EU citizenship from people who are current EU nationals.
European court judgments make it clear how hard it is to remove that citizenship, so if a member state breaks up it is unclear whether that takes away EU citizenship. This has led to a legal argument running against the "international law" argument, that if an independent Scotland were outside the EU, this would unlawfully deprive Scottish EU citizens of their rights.
Scotland would not be an accession country and would therefore remain part of the European Union. There is now a new clause as a result of the Lisbon Treaty that requires negotiation for a Member State to cease to be in the EU, and we know from the Greenland precedent that negotiation is also required for part of a Member State to withdraw. So the argument from Westminster that Scotland would be excluded is inaccurate.
This view has been fully supported by a range of EU experts and academics.
Eamonn Gallagher, former director general of the European Commission and EC Ambassador to the UN in New York, has said: "Scotland and the rest of the UK would be equally entitled to continue their existing full membership of the EU." (Sunday Herald, 18 February, 2007).
Emile Noel, the first and longest serving secretary-general of the European Commission has said: "Scottish Independence would create two new member states out of one. They would have equal status with each other and the other states. The remainder of the United Kingdom would not be in a more powerful position than Scotland."
Lord Mackenzie-Stuart, a judge on the European Court of Justice between 1973 and 1988 and president from 1984 to 88, has said: "Independence would leave Scotland and something called 'the rest' in the same legal boat. If Scotland had to reapply, so would the rest. I am puzzled at the suggestion that there would be a difference in the status of Scotland and the rest of the United Kingdom in terms of Community law if the Act of Union was dissolved." (Scotland on Sunday, 8 March, 1992).
Aidan O?Neill QC said on the Eutopia Law blog on citizenship (14 November, 2011): "Rather than analyse the matter from the classic viewpoint of public international law ... EU law requires one to look at the issue from the viewpoint of the individual EU citizen ... the question to ask is whether the CJEU would consider that the fact that Scotland became independent required that all (or any portion) of the previous UK citizenry thereby be deprived of their acquired rights as EU citizens?"
(3)The last answer is the least likely and least credible ? somewhere, there has to be at least one successor.
m.guardian.co.uk/commentisfree/2012/sep/13/independent-scotland-eu-member-snp?cat=commentisfree&type=article
www.yesscotland.net/independent_scotland_will_not_have_to_reapply_for_eu_membership