My Lords, I wish to address Amendments 152, 197 and 206, on the matter of the customs union. Before I do so, perhaps I might be permitted to say a word of admiration about and pay tribute to the people outside this building—many of them waving British as well as EU flags—who have been there for several months, hoping to impress on us the importance of the case. We in this House—from the comfort of these Benches—should not be tempted in any way to neglect or slight efforts made by our citizens to bring their concerns to our attention. I have been most impressed by them. I have often spoken with them; one young lady, on a very modest salary, told me that she paid quite a lot of money on a fare from Manchester and was sleeping on a friend’s floor in order to stand for 12 hours outside this House. Her account was very typical. I counted more than 140 people one evening, when the temperature was getting very close to zero. I believe that sort of dedication and selfless concern for the future of the country is most impressive.
I am well aware that many of my colleagues in the House have come to this debate in the belief that they are carrying out an instruction from a referendum. I reject entirely that concept, which clearly contradicts the idea of a sovereign Parliament. By definition, if a body is sovereign, it cannot receive instructions from anyone. That is a matter of definition; it is what philosophers call an analytic truth. Even more absurd would be the idea that we could take instruction from a referendum in a previous Parliament. Heaven knows what Parliament would be subject to after a certain period in which we adopted that proposal. One can easily see to what ridiculous results that would lead. It would also make a nonsense of the fundamental principle of our constitution that no Parliament can commit its successor, and if you abandon the concept of parliamentary sovereignty and the belief that goes with it that no Parliament can commit its successor and therefore every Parliament after a general election can open a new page, there will be very little left of our constitution that people who take that line will still believe in.