A comment often made by those opposed to electoral reform is that voting systems isn't something they hear about 'on the doorsteps', and no it isn't. However, the voting system used to elect our MEPs, MPs, MSPs or councillors affects every one of those issues that do exercise the minds of voters.
That's because in many cases the voting system used can encourage us to vote for people who are most likely to keep out those we don't want, rather than vote in those we do. Take for example, the current debate ahead of this week's referendum, on whether to change the current First Past The Post (FPTP) system used to elect MPs to Westminster to Alternative Vote (AV).
Now I don't think changing the system will greatly alter the number of MPs of each party elected. What it will do though, is to remove the tactical vote so often encouraged by candidates who came second in a particular constituency last time ("It's a two horse race", "a vote for x is a wasted vote", "Winning here").
There is a humorous, but excellent video of how AV works, using the example of how cats, which would never consider voting for a dog, would find their votes split under FPTP - letting in the dreaded dog - but not under AV. Any voting system which encourages voting for a candidate other than the one you really want is flawed and deciding who others are likely to vote for shouldn't be part of the decision making process, but under FPTP it is - otherwise you may find your vote is wasted.
A move to AV would encourage more candidates to stand, particularly those with similar views. Take for example the far left - SSP, Solidarity, Socialist Labour, Respect, SWP to name but a few. In some places, a candidate from the far left may be preferred by the electorate, but if all these parties stand against each other, under FPTP the Tory may even be elected, despite being generally disliked (a single dog up against many cats). With AV, that simply won't happen.
In the cats and dog analogy, supporters of FPTP maintain that the cat which wins under AV is less popular than the dog. I doubt if many would agree. They also argue, erroneously, that under AV, voters whose votes are transferred get more than one vote. What actually happens under AV is that there are several rounds of voting - and those who voted for the dog also get to vote in each round - it's just their vote isn't transferred.
Another argument the No to AV camp uses is the cost of switching to AV (which is also flawed as it includes the cost of the referendum itself - money already spent - and the use of counting machines, which aren't needed). However, if we had a voting system (as in Scotland) which reduces the likelihood of a single party gaining an overall majority on a minority of votes, we could dispense with the House of Lords, an unelected body set up to act as a moderating influence on the House of Commons. We get by without such a chamber in the Scottish Parliament, so why not at Westminster?
Ideally, we should have a fully proportional electoral system for Westminster, and the Single Transferable Vote is my choice for that. Although AV is an improvement on FPTP, AV is not proportional. However, moving from AV to STV is simple - just merge constituencies together and hey presto! As far as the voter's concerned, there's little change - just mark your preferences 1,2,3, etc in the same way. Even Casual Cat could approve of that.