Read this: Ireland, the United Kingdom and the three Crown Dependencies are all parliamentary democracies, with their own separate parliaments. All parts of the United Kingdom return members to parliament in London. In addition to this, voters in Scotland, Wales and Northern Ireland return members to a parliament in Edinburgh and to assemblies in Cardiff and Belfast respectively. Governance in the norm is by majority rule, however, Northern Ireland uses a system of power sharing whereby unionists and nationalists share executive posts proportionately and where the assent of both groups are required for the Northern Ireland Assembly to make certain decisions. (In the context of Northern Ireland, unionists are those who want Northern Ireland to remain a part of the United Kingdom and nationalists are those who want Northern Ireland join with the rest of Ireland.) The British monarch is the head of state for all parts of the isles except for the Republic of Ireland, where the head of state is the President of Ireland.

What type of system does Southern Ireland use to make decisions?
What is the answer? (If it cannot be answered, return "unanswerable")
unanswerable