Single Transferable Vote

• Where is STV used?

  Northern Ireland Assembly
• What does STV use?

  Multi - member constituencies. In the case of the NI Assembly, there are 18 consistencies, each returning 5 members
• How does STV work?

  Voters rank candidates in order of preference on the ballot. In order to be elected, a candidate needs to achieve a quota, arrived at using the Droop formula.
• How does the transferring surplus votes work?

  When a candidate has more votes than needed to win (a surplus), their extra votes are transferred to other candidates based on voters' next choices. This ensures that every vote counts towards electing someone else, even if the first choice has already won.
• Advantage 1: Highly proportional system

  There is a very close correlation between votes and seats
• Advantage 2: High voter choice


  Voters can choose between candidates standing for the same party, as well as between candidates from different parties. They also rank their candidates preferentially, effectively giving them multiple votes
• Advantage 3: Northern Ireland Specific

  It has created power sharing governments which allows representatives of the two rival communities to work together, helping to end 30 years of the Troubles. These governments always have majority support
• Disadvantage 1: large multi member constituencies

  The member constituency link may be weak
• Disadvantage 2: prone to conflict

  Power sharing governments may bring rival groups together but they’re still prone to conflict. The Northern Ireland executive has been suspended several times and STV didn’t help the more centrist parties in the long term. The DUP and Sinn Feinn now dominate, replacing the more moderate parties since 2007. Voting across community lines is still rare
• Disadvantage 3: Counting votes is slow and the results are difficult to understand
• Disadvantage 4: It can lead to donkey voting

  In the 2019 local elections in NI, in Distract Electoral Areas where there were two candidates running from the same party, the candidate whose surname was first alphabetically was elected 85 % of the time whilst the second candidate on the ballot paper was elected only 54 % of the time