European Union Bill

My Lords, I want Turkey and other states to accede but, like many others, I worry about whether a referendum would yield a yes vote. However, I must not emulate certain others and come down against referendums in this area for fear of the result. That indeed would be sinful. I want convincing arguments as to why referendums on accession treaties should be excluded, and I am worried about the strength of the arguments advanced so far. In particular, what about immigration? Do we not, when we agree to an accession treaty, cede more power to control immigration into this country? That is what worries me. I would just like an answer from my noble friend on that point.