STV offers choice for and choice against

Prof Andrew Geddis. Photo: ODT files

Our local voting papers are now with us and it's time to choose who we want to run our city (and our region, and our DHB, etc). For some of those elections, we have to use the Single Transferable Vote (STV) method.

Voting with STV really isn't hard. You just have to rank people in order of preference. If you think Candidate A would represent you better than Candidate B, then you give the first a higher number than the second.

So, if there are 10 (or 12, or 17) people you think would make good elected members, then all you have to do is list them in order of preference. Ranking those candidates that you positively approve of does as much as you can to ensure that they will be successful.

Of course, there's no guarantee all (or even any) of them will get enough support from other voters to get elected, but at least your vote has helped them as far as it can.

But what if, like me, you don't just want to help elect the candidates that you like? What if, like me, there are some candidates running who you really don't want to see on the council?

They may be councillors that you think have done a lousy job and so need to be moved on. They may be individuals that you know (or have been told by someone that you trust) would not be good for the city. Some candidates' campaign statements about the policies they want to pursue may fill you with horror.

How can you use your vote to not only help elect those candidates you like, but also keep out those candidates you really don't like? Doing so involves a bit more time and effort on the voter's part, because it requires ranking all 37 council candidates.

You see, the STV voting system used in Dunedin can count your vote as long as there are still council places to be filled. You don't really need to know how it does so, just that it can.

However, if your vote runs out of ranked candidates - either they have already been elected, or have dropped out of the calculation because they didn't get enough support - then it will stop being counted for any unfilled council places.

Note that this can happen if you've ranked 14 candidates, or even 20 or more. Some of the candidates you have ranked may get so little support that they are removed from the counting process and so, even though unfilled places on council remain, your vote has nowhere left to go.

Once your vote exhausts its preferences in this way, you get no say on who gets the remaining council seats. So, even if there are people you really, really don't want to win them and would rather anyone else did instead, your view won't be taken into account.

Therefore, this is my advice for all those who, like me, don't just want to elect the candidates we like but also stop those we don't like.

First of all, sit down and list all those candidates you would positively like to see on the council, ranking them from best to least-best. Then, list all those candidates you really don't want to see on the council and rank them from worst to least-worst.

On your voting paper, you then rank your ``liked'' candidates from 1 on down to whatever your least-best candidate number is. When you've done this, you've done as much as you can to help them get elected.

But then you should rank your ``disliked'' candidates from 37 on up to whatever the least-worst candidate number is. Doing this makes sure your vote won't help elect someone you dislike, as long as another candidate that you like more remains in the running.

If you are like me, this will leave some candidates whom you don't have any feelings for, either way. If you really don't care which, if any, of these individuals gets on to council, you can randomly rank them in the places between the liked and disliked candidates.

Following this method of using your STV vote has one advantage and a couple of admitted disadvantages.

The one advantage is that by following it, you are doing as much as you possibly can to ensure your vote will help those you most want to be mayor or on council, while stopping those you most dislike from getting elected.

The disadvantages are that it requires a bit more time and care on the voter's part. You need to think about not only who you want to represent you, but also who you don't want to do so.

And voters also need to be careful that they don't accidentally give two of the various candidates the same preference. If this happens, then the voter's vote can't be counted beyond this point (although it still counts for all candidates ranked above it).

However, for anyone who is interested not only in getting their preferred candidates elected, but also doing as much as they can to stop those they don't want to be their representative, this is the best way to do so.

- Andrew Geddis is a professor in the Faculty of Law at the University of Otago.