The Problem with First-Past-the-Post Voting

First-Past-the-Post voting is a terrible idea. On paper, the candidate getting to win an election with the most votes sounds like a fair and straightforward type of voting system. In practice, what you actually have is a plurality being favored at the expense of the majority. How could this be? Why would a plurality be favored at the expense of the majority?

Let’s start off with this scenario. You have seven different colored candidates running for office as follows: Red, Orange, Yellow, Green, Blue, Indigo, and Violet. Orange gets 13% of the vote. Green gets 18%. Red gets 19%. Indigo gets 9%. Blue gets 20%. Violet gets 6%. Yellow gets 15%. Under the rules of First-Past-the-Post, Blue wins the election and gets to rule for the length of the established term. Here’s where the first problem starts: minority rule. A majority comprised of 80% of the total voters who actually turned out for the election wanted another candidate to hold office. There were only seven candidates in this example, but if you imagine that there had been twenty candidates, Blue might have only gotten 5% of the vote and still get elected.

But this problem with minority rule is just the beginning. The second problem with First-Past-the-Post is that if enough time passes, it results in an inevitable and unavoidable two-party system. How does this happen? To answer this question, we will have to see what happens over several election cycles. The Blue candidate’s term in office has expired and it’s now election time once again. Only this time, the voters remember the results from the last election. This new information will change how they will now behave. The Indigo and Violet voters, in particular, will have to face the reality that they backed candidates who were too extreme in their views and therefore too unappealing to even have a shot at winning the election.

The Violet voters, who were unhappy with Blue’s government, decide to back the candidate with the best chance of winning the election, Red. The Indigo voters want to vote for Yellow because Yellow’s message of freedom and prosperity resonates with them, but are afraid to do so because the Blue candidate is running negative campaigns against the other competitors. Indigo voters, not liking the idea of a Red government, vote strategically for Blue. The final results are that Blue gets 26% of the vote and Red gets 28% of the vote, making Red the winner of the election.

Indigo and Violet, seeing how poorly they performed and how needlessly expensive their campaigns have been, decide to drop out of the election. They see that all their hard work at running for office was for nothing so they drop out of more races in the future. What started out as a seven-party system is now down to five players in the game. Fast-forward to the next election and you have only five candidates running. Again, the voters remember what happened last time.

In this election, it’s Orange voters who recognize that their candidate cannot win. As they are centrist voters who are less ideological than the rest of the other voters, they don’t really like either Red or Blue. Both the Red and Blue candidates know this, so they each run negative election campaigns to capitalize on the biggest fears of the centrists. The Orange voters split their vote and are mostly voting against the candidate that they don’t like rather than voting for the candidate that they do like. After this election, Red gets 33% of the vote and Blue gets 34%, making Blue the winner of the election. Orange, as with Violet and Indigo, drops out of the race.

In the final election we will look at, Green and Yellow voters are unhappy. They both really like the candidates that they supported in the first election, but they now realize that they have to compromise on their choices. The Green voters agree with Blue on some issues while disagreeing with others, but they really don’t like Red. And the Yellow voters agree with Red on some issues while disagreeing with others, but they really don’t like Blue. They strategically abandon their actual preferred candidates in a classic example of strategic voting out of fear that the one candidate that they disagree with the most will win the election and hold office. The final results are Blue at 49% and Red at 51% with Red winning the election. Green and Yellow are the last candidates to drop out of the race and now we are left with a two-party system.

Because of sway-able, centrist Orange voters, the only parties with actual electoral viability are Red and Blue. But the two parties never change, except in some extremely rare circumstances that results in one of the two parties being replaced with a new one. The voters ended up with this system, not because they were lazy voters or because its what they genuinely wanted to have, but because of the mathematics of how the system had been set up. Inevitably, when enough time passes, all First-Past-the-Post systems lead to two main parties being capable of winning an election and holding office. But the choices of the voters still hasn’t changed since that first election.

Only two-fifths of them want either Blue or Red as their first choice and three-fifths of them want someone else as their first choice. It’s this majority of the voters that become disinterested in the democratic process because they have no meaningful way to express their real preferences. But it only gets worse from here. If the voters are divided into groups before they vote, they are susceptible to gerrymandering. Gerrymandering is when you change the boundaries of an electoral zone in order to change the outcome of an election. CGP Grey has already made a YouTube video here explaining how gerrymandering works in detail, so I won’t waste my time and get sidetracked with another topic. Now that you know what gerrymandering is, let’s resume. Which brings us to our final question.

If the system is so bad, why can’t we vote for a third party and change the system? This brings us to the last and worst problem with First-Past-the-Post voting—The Spoiler Effect! Imagine that after years of rule by Red and Blue, Yellow decides that it’s time to enter the race and thinks that the voters are tired of the status-quo and that there is finally a shot at winning the election. But Yellow only gets 15% of the vote mostly from Red voters. Blue easily beats Red and wins the election. This situation shows the First-Past-the-Post system at its worst. The better a third-party candidate does, the more it hurts a candidate’s own voters by guaranteeing a loss for the party they like the most and a win for the party they like the least.

So, how should we make a new voting system to replace First-Past-the-Post voting? Well, we shouldn’t have to worry about minority rule. We shouldn’t have to worry about being incentivized to vote against candidates that we don’t like rather than voting for candidates that we do like. We shouldn’t have to worry about an inevitable two-party system. We shouldn’t have to worry about gerrymandering. And finally, we shouldn’t have to worry about the spoiler effect harming third-party candidates in elections. A new voting system needs to have all of these considerations in mind.

Thank you very much, CGP Grey, for educating me on how the mathematics of voting can change the outcome of an election!