Denseman on the Rattis

Formerly known as the Widmann Blog


Another reason to dislike first-past-the-post

Labour vs. LibDemsOne thing I really dislike about the first-past-the-post voting system is that some parties are inherently favoured.

This is due to some parties having their votes concentrated in really few constituencies, while other parties are scattered loosely across the country.

Have a look at the graph on the left.

Using Electoral Calculus‘s user-defined poll, I tried to hold the Tories steady at 40% of the vote and then try to put in decreasing values of Labour support going from 26% to 14%, and increasing values of LibDem support from 14% to 26%, so that the two parties all the time add up to 40%. The two parties’ share of the vote is shown as the small boxes at the bottom.

The lines show the number of MPs that the two parties would get.

When both parties are getting the same number of votes, Labour get 156 MPs compared to the LibDems’ 56.

And it’s not till the LibDems reach 25% of the vote and Labour are down at 15% that the former actually get more MPs.

This is basically because the LibDems and Labour compete in very few constituencies.

When Labour lose their votes, the seats are picked up by the Tories, the SNP or other parties, but not very often by the LibDems.

And when the LibDems get more votes, they start winning seats from the Tories, typically rural seats in England, but because I kept Tory support fixed in this example, that was hard.

I know this is a simulation, and it might not reflect real life. If the LibDems were to overhaul Labour, it would probably be partly because of urban voters switching.

Nevertheless, I find the whole system very undemocratic. Surely if one party gets more votes than another party, it’s only fair that it would also get more MPs!

4 thoughts on “Another reason to dislike first-past-the-post

  • What will happen the next time, where you’re likely to end up with a parliment without a single majority party? Won’t that be a good time for the liberal democrats to get proportional voting in place instead?

  • I consider a hung parliament fairly unlikely. It’s another unfortunate property of first-past-the-post that it is highly unstable: A small change in the number of votes will typically either lead to almost no change in the number of seats, or to a complete landslide.
    And even if a hung parliament were the result, all the LibDems are likely to get is a referendum on a new voting system, and that is likely to fail if both Labour and the Conservatives campaign against it.
    That said, all other elections in the UK use different systems, so perhaps one of them will take over eventually.

  • Brown is very good at proposing things, but also very good at ensuring that nothing will ever happen.
    I’d be happy to be proven wrong, though. 🙂


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