Three First Ministers Signed a Declaration of Self-Determination. None of Them Can Call a Vote.
The leaders of the SNP, Plaid Cymru and Sinn Féin, who are now the first ministers of Scotland, Wales and Northern Ireland, signed a joint declaration in Cardiff on Monday asserting their nations' right to self-determination. The UK prime minister has already ruled out referendums in Scotland and Northern Ireland. The power to hold one sits with Westminster in every case.

