of the island of Ireland alone, by agreement between the two parts respectively, to exercise their right of self-determination on the basis of consent, freely and concurrently given, North and South, to bring about a united Ireland, if that is their wish".

Indeed, the Declaration addressed the "boundary question" of who would be allowed to vote in a referendum, which it stated the people of the island of Ireland. Therefore, the idea of self-determination gave legitimacy to any constitutional decision taken by the people of the island