Short answer
The Secretary of State for Northern Ireland. They must call a poll if it appears likely that a majority would vote to leave the UK and join a united Ireland.
What we know Fact
- The rules are in Schedule 1 of the Northern Ireland Act 1998.
- The Secretary of State may call a poll at any time, and must call one if it appears likely a majority would vote for a united Ireland.
- There must be at least seven years between polls.
- The last border poll was held in 1973.
What is still unclear Interpretation
The Act does not say what evidence the Secretary of State should use to judge how people would vote. Census results, election results and opinion polls can point in different directions, and none is named in the law.
Sources
Our view Pro-Union
The decision belongs to the people of Northern Ireland, and the bar is set by law. Those asking for a poll should first set out exactly what a united Ireland would mean for health care, pensions, taxes and jobs. Until they do, the case for change has not been made.
