Simon Coveney (Cork South Central, Fine Gael) | Oireachtas source

That is a very reasonable set of questions. There was a choice to be made here as to whether we would put in place a formal legal treaty on the common travel area on a bilateral basis between Britain and Ireland or whether we would do it through this memorandum of understanding, which would have some legislative element to it. I understand we chose the memorandum of understanding mechanism to have the flexibility to deal with the kinds of potential issues the Deputy has raised. I am not suggesting they relate to spouses. As a result of the fact that the common travel area was in some ways quite a loose arrangement, we did not have a single item of legislation which addressed it in total; it went across multiple items of legislation. It built up as an understanding between the two countries over decades.

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