Professor Colin Harvey:

There is also a wider lesson which resonates for the debate on human rights. One of the challenges learned from the Good Friday Agreement, the British-Irish Agreement, is that people have been saying for a long time that aspects of it have not been implemented or enforced. There is very little we can do about that. Domestic law in the UK - the British constitutional context - really matters given the peculiarities of the British constitutional system. One of the challenges of the Good Friday Agreement, the British-Irish Agreement, was what to do if there is a breach in domestic law within the UK. That has informed the debate around the negotiations with the EU and the discussions on the withdrawal agreement, the protocol and everything else. In terms of the conversations we are having on rights, it is no good thinking one has paper rights if they are not enforceable. That applies to the broader human rights conversation. That is really important for the future UK that is out of European Union, where we lose that European Union background and framework. The important lesson in all this is to make sure the rights one has signed up to are enforceable and one can do something about them. Brexit is exposing that and people are trying to learn the lessons from that.

To switch to a separate conversation, a similar issue arises with the common travel area. The Commission's work has pointed this out. People talk about the CTA as if it is a thing but what research has found, and the Commission has pointed out, is that it is built on sand, legally. It needs to be codified and written down. The reason people are emphasising a treaty is that we need not just to think what are the rights but what to do about them. Irish citizens in the North and Britain need to know that in 20 years' time, without exaggerating this, they will not end up in a Windrush scenario in a British or Northern context. The Deputy's question is exposing that sharply.