So you’re voting in an STV election, and you want know how to best use your vote? Well … here goes.
What is STV?
STV is Single Transferable Vote. It is a voting system where everyone gets one vote, but that vote, or part of that vote, can transfer from one candidate to another candidate. It can be used to elect one candidate – like a mayor – or to elect multiple candidates in a single ward. It is generally considered a proportional voting system.
What elections use STV?
All District Health Board elections use STV, as well as a number of City Councils, including Wellington, and Dunedin. The system used in the other elections is called first-past-the-post or block vote. Everyone will have a combination of the different elections that they can vote in, and you don't have to vote in all of them if you don't want to.
How do you vote in an STV election?
You rank the candidates with numbers. Put a 1 next to the candidate you most want to win, a 2 next to your next favourite, then a 3 for then next person and so on.
Do I have to rank everyone?
No. Your vote is still valid even if you only rank some candidates.
What are the ways my vote might become invalid in an STV election?
If you don’t rank anyone at all with a “1”. Or if you rank more than one person with a “1”. Or if you vote using ticks, like in a first past the post election.
If you muck up the later numbers – like ranking two candidates with “3”s – your vote won’t be able to transfer to help them or anyone lower, but your earlier rankings will still count.
But is it a good idea to rank everyone?
But if I give someone I don’t like a rank, couldn’t this hurt the chances of candidates I like more?
Your lower preferences cannot ever harm the election prospects of anyone you rank higher than them.
But some of my vote could still go to someone I’m not a fan of?
Yes. But only if all the people you ranked higher than them have already been elected, or cannot possibly win.
By ranking a candidate lowly, you’re not helping them beat people you like more than them, you’re only helping them against people you hate more.
In the 2002 French Presidential election, there was a vote-off between the top two candidates, the right wing incumbent Jacques Chirac, and far right National Front leader Jean-Marie Le Pen. Many left-wing voters did something they never thought they would do, and voted for Chirac. They weren’t using STV, but the principle is identical. In Australian Senate Elections, and some state elections – which do use STV – the Labor Party has advised its supporters to rank the right-wing Liberal Party above Pauline Hanson’s One Nation Party. Voting this way doesn’t hurt the Labor Party, but it makes it as unlikely as possible that One Nation gets anyone in.
Like the French voters who “voted for the crook, not the fascist”, ranking all the candidates helps ensure that what you might consider “the greater of two evils” won't be elected.
But what if I really don’t want to rank everyone?
You don’t have to. If there are a bunch of people whom you think are just as bad each other, or you know nothing about, your vote will still count. If the election comes down to race between people you haven’t ranked, you won’t help determine the result, but if you don’t mind which of them is elected, this shouldn’t bother you too much.
But if there’s someone I really really don’t want elected, I should rank everyone else above them?
And this can’t cause any damage?
Well, you could be wrong :-)
It’s always possible that the one the person you think you want to make sure isn’t elected isn’t actually the worst candidate. Maybe that candidate you haven’t heard of is really George W. Bush after a name change, and if you knew that then he’d have been your absolute last choice. If you’re casting your vote for someone you know very little about, there’s always a chance that if you had known more about them, you’d have thought differently.
An informed vote is always a good idea.
Even for the District Health Board?
Okay, you got me. Health Board elections are stupid.
Seriously though, how does the counting work?
I won’t go into it in great detail, but...
First, all the number 1’s are counted.
If it’s a one-person race – like an election for mayor – then someone has to get more than half of the votes. If no-one does, then the candidate with the lowest number of 1’s is declared to have lost. All the second rankings for that candidate are then added to the votes for the other candidates. The votes of anyone who voted for that losing candidate that didn’t have a valid second ranking are set aside.
If anyone now has a majority of the remaining votes, they’re elected. If not, the person with the lowest number of votes is declared to have lost, and the second rankings of the people who voted them number 1 are added to the votes of the other people. If anyone voted the first loser as number 1, and this candidate as number 2, then their third preference is added instead. If anyone who voted number 1 for this candidate, had their second choice as the candidate who was kicked out in the first round round, then their third preference is used.
This keeps going on, until someone has more than half of the remaining votes.
But what about in STV elections where you’re electing more than one person?
Multi-member seats operate on the same basic principle, but with a couple of extra twists. Instead of needing more than half the votes, candidates need to beat a quota, which is set so that only the right number of candidates can be elected. In a one-person race, this is more than half, because it is impossible for two or more people to both get more than half of the votes. If your ward is electing two people, the quota is set at just over a third of the votes; if it’s five people, then it’s just over one-sixth of the votes.
The main extra twist is that the vote counting continues after candidates have already won. If your ward is electing three people, the votes keep transferring until three people are elected. There’s also an extra step. Before the lowest-ranked person is declared to have lost, and the second preferences of the voters who voted for them are distributed, the excess votes of anyone who has already gotten past the quota and been declared a winner are distributed.
For example, if the quota was calculated as being 100 votes, and on the first round, one of the candidates got 125 votes, then those excess 25 votes are distributed according to second preferences. To make it fair, the second preferences of all that candidate’s voters are used (not just the last 25!); this would mean that an extra 0.2 votes would be added to the second choice of each of the voters that had chosen the winning candidate as their first preference. Only once this is done, is the first loser declared not to have been elected, and are their second preferences distributed. The fractions of votes can get pretty complicated (you might have 0.75 votes going to your first candidate, and 0.20 votes going to your second choice, and 0.05 votes going to your fifth choice), so all the ballots are uploaded to a computer which goes through the calculation.
Is that all?
It’s way more than you need to know to cast an informed vote, but if you do want more detail, there’s a handy government website which explains STV for you took look at.
Don’t forget to vote!
Your voting papers have to be with your local returning officer by midday on Saturday October 9. If you’re posting them back, try to get in the post on or before October 6, to make sure there’s enough time. Otherwise it might be safer to drop them off in person at the council, or somewhere like a public library – your council website – and voting papers – should have all the information you need to do this.