By Nick McDermott
Published November 1st 2003 in The Guardian
The 108-member assembly is elected using the single transferable vote (STV), a system of proportional representation. Six members of the legislative assembly are elected from each of the existing 18 Westminster parliamentary constituencies.
How does STV work?
STV is a proportional representation system that allows voters to select individual candidates rather than party lists. Voters rank the candidates in order of preference. First-preference votes are the first to be looked at. Votes are then transferred if necessary from candidates who have either been comfortably elected or from those already eliminated from the election.
How is the first minister selected?
The first minister and the deputy first minister are elected by the cross-community "parallel consent" voting procedure. To be elected into office, the first minister and the deputy require the support of 50% of registered nationalists and unionists as well as a majority of the assembly.
If the first minister is deposed as leader of his party he or she does not automatically cease to be head of the executive. The first minister can only be deposed if a majority of nationalists support unionists in removing him.
How is cross-party balance achieved?
Parallel consent voting forces unionists and nationalists to nominate moderate candidates acceptable to at least a majority of the other party's members in the assembly. Each side has the power to veto an unacceptable hard-line candidate. In effect, the rules ensure that a unionist and nationalist share the top two positions.