Christopher Howarth is a senior researcher working in the House of Commons. Prior to this he worked for Open Europe, as a Conservative Foreign Affairs Adviser and senior researcher to a Shadow Europe Minister.

You would be forgiven for thinking we had few remaining EU vetoes to give up, yet back in February we managed to trade one of the very last in return for David Cameron’s EU deal.

For contrary to the impression given, our EU partners did not spontaneously agree to create a “reformed EU” – the reforms were minor and not voluntary – it was a straightforward old fashioned EU deal. We had something they wanted and in return the Prime Minister got what he wanted – the illusion of reform.

What we traded was our veto allowing us to stop the further Eurozone integration seen as necessary to try and make the Euro work. If we vote to remain this deal will now play out, but not necessarily as envisaged.

This is because the legally binding nature of some parts of the deal are more certain than others. It is possible we may end up without the minor concessions that the Prime Minister was promised, yet simultaneously have already given up our ability to argue for more comprehensive reform by wielding our veto at the time of the next EU treaty change.

The worst of both worlds – in the EU but with no influence over its future direction, despite the probability that further Eurozone integration, backed up by their 65 per cent plus majority vote, will end up affecting the UK.

Cameron set out the nature of the trade in his seminal Sun May 2014 interview with Grant, a London taxi driver:

“They need the treaty change. The Germans and others need a banking union and a fiscal union, so just as they need some changes I am perfectly at liberty to say, ‘All right guys, you can have some changes.’ But I need some changes too.”

This was summed up by the French President straight after the agreement:

“Today, the United Kingdom has a special place in Europe but there was no exception to the rules of the single market, there are no planned revision of the Treaties and no right of veto over the Eurozone.”

So taken in two parts, how binding is our surrender of the veto and secondly, how legally enforceable are the commitments we gained in return?

How binding is the UK’s commitment not to block Eurozone integration?

These commitments are contained in the February Decision of the EU. This was not an EU treaty but the Prime Minister has confirmed it is legally binding and has the status of an international treaty. The following are therefore as binding on us as is any other treaty:

  • We “shall not impede the implementation of legal acts directly linked to the functioning of the euro area”.
  • We “will not create obstacles to but facilitate such further deepening”.
  • We will “refrain from measures which could jeopardise the attainment of the objectives of economic and monetary union”.
  • We pledge “mutual and sincere cooperation” with the Eurozone.

Further to this, we have agreed that “the substance of this” will be placed in the EU treaties in the future meaning the European Court will have full jurisdiction over the interpretation and enforcement our commitments.

Can the UK rely on the promised reforms materialising?

These reforms amount to a short list (for more detail see ConservativeHome here) but even so there is no guarantee they will be delivered:

  • Non-discrimination for Non-Euro states: The key ‘commitment’ to the UK, although the EU was already bared from discrimination. Without treaty change these commitments are not enforceable on the ECJ, the European Commission or Parliament.
  • Emergency non-Euro pause of financial regulation: This will become a European Council Decision after the referendum. It will not change the EU Treaties or the Qualified Majority Voting system and cannot be guaranteed to actually block a measure.
  • Red Card for EU National Parliaments / Ever closer union: The ‘Red Card’ was hardly worth the effort, will be highly limited and relies on the EU28 respecting it. The statement stating the UK is not committed to further political integration is unlikely to be respected.
  • Migrant welfare measures: For these to come into force, the EU28, Commission, Parliament and ECJ must all agree. There is no guarantee that any or all of these bodies will actually pass or respect the secondary legislation required. The Court, Parliament and Commission are not bound by the agreement.

So what happens if the Eurozone comes forwards with Treaty change?

If there is a new Treaty negotiation, there will have to be a fresh negotiation to untangle the conflicting aims in the agreement and agree precise Treaty wording.

This will be a negotiation where the UK has already conceded the principle of Eurozone integration (within EU structures) and would find it exceedingly hard to walk away or raise any additional reform proposals. This would be the worst of all worlds, not in the Euro, run by the Euro – and where the last remaining door shut on 23rd June 2016.