Thread by @jeuasommenulle

A thread on why the “Vienna Convention trick” could solve the Brexit impasse. In a nutshell the idea is the following: instead of having a unilateral way out of the backstop, the UK would have a unilateral way out of the entire WA. 1/n

You can easily see how it solves everyone’s problem: from the EU’s pov, there is a signed deal and the worst-case scenario is that the UK votes to get back to the other option, which is no deal anyway! 2/n

Moreover, that UK vote is very unlikely (they can’t agree to anything!) and some cash would have already been paid! 3/n

From the UK’s pov it’s also good: hard Brexiters and haters of the backstop know that UK isn’t trapped forever, softer Brexiters care more about the future relationship anyway. 4/n

So can it be done and, more importantly, can it be shown reasonably that it works (the fact that it actually works in the future is somehow irrelevant – what matters is what people think.) 5/n

This is where it gets tricky. The first difficulty is whether Vienna convention (“VC”) applies at all. Two problems here 1) EU is not a party to VC and 2) ECJ has always claimed that EU law is sui generis and EU treaties are not subject to VC. 6/n

BUT on 1) post WA, even if VC does not strictly apply, customary international law still applies as EU treaties do not apply and on 2) it’s unclear whether an agreement to exit a treaty operates under that treaty’s legal order. 7/n

SO I think it can reasonably be argued (and that’s the only thing that matters here) that if VC does not apply, at least the basic customary international law principles still apply to the WA. 8/n

And the VC is mostly an exercise in clarifying and making explicit those principles, it doesn’t add much to the principles themselves. 9/n

So when can a country exit a treaty if there is no exit clause in the treaty? 10/n

Broadly speaking, there are two general cases: 1) if it can be shown that the parties intended to allow such possibility and 2) if the nature of the treaty demands that it should be possible. 11/n

The convention and international law also allow for withdrawal in some specific scenarios: the object of the treaty is now meaningless, exceptional and unforeseen changes of circumstances, new treaty, new international norm, etc. 12/n

I don’t think any of those are really relevant because, by definition, they cannot be foreseen and thus do not reduce the risk of being indefinitely “trapped” in the WA. 13/n

So what about the general case? Treaties from which exit is not possible are generally considered to be stuff like status of a territory, peace treaty, new border, etc. Clearly the WA seems out of this scope. 14/n

Treaties for which exit should be possible are stuff like commercial treaty, military alliance, econ co-operation, arbitration or settlement. Not clear that the WA is in there either 15/n

So what happens for treaties which are not in either category? Well, Waldock in his ‘Second Report on the Law of Treaties’ says that : 15/n

“Treaties not referenced in either list would be subject to a presumption against withdrawal ‘unless it clearly appears from the nature of the treaty or the circumstances of its conclusion that it was intended to have only a temporary application” 16/n

Can you spot the magic word? “Temporary”! Just like the backstop which is supposed to be “Temporary” 17/n

So it seems to me that it’s a reasonably good argument to say that the WA can be unilaterally terminated with some notice because it was intended to be temporary. 18/n

On top of that, if the EU did not object to some statement about this (and not only about the backstop) it could provide some comfort to the thesis that “the parties intended to allow such possibility” 19/n

The possibility of unilateral termination of the WA is discussed by MPs in researchbriefings.files.parliament.uk/documents/CBP-… 20/n

But I think this discussion misses the main point which is that exit could be allowed not based on unforeseen change of circumstances (by definition you cannot know that this will be possible!) 21/n

Nor based on a breach by the EU (again, you can never be sure of that) but that the treaty is intrinsically a treaty which should allow termination. 22/n

And if the EU did not object to such an interpretation made by the UK, it could be enough to get the deal done as, again, this is still better than no deal – for everyone! End 23/n

curious to hear the views of much better legal minds than mine e.g. @StevePeers @JolyonMaugham or @davidallengreen , but bearing in mind that this would not have to really work, it would just require that it can be reasonably argued that it would work...

@Sime0nStylites @odtorson enjoy :-)

@tconnellyRTE i think this route is more consistent than the "unforeseen change" route which as you point is self contradictory