How Well Does Ranked Choice Voting Work?
After analyzing the US legislature elections in my previous article, it appeared that changing from a winner-take-all voting system to ranked-choice voting (RCV) would help improve several problems with US legislatures. Namely, it should reduce over-representation of the majority and increase the choice of candidates. In order to see if this is true, I analyzed how RCV performed in Ireland’s 2016 elections.
Members of Ireland’s lower legislative house, the Dáil, have been elected using RCV since 1921. The country is split into constituencies that elect 3 to 5 deputies each, depending on the population in each one. The variable size of constituencies allows for boundaries that better follow county borders rather than forcing voters into groups of equal population.
Greater Competition In Elections
The official results for the election can be found here. In the 2016 election, no single party won a majority of seats. The Fine Gael party ended up with the most, with 50 out of 157 seats. In all, eight parties won seats in the Dáil plus a further 19 deputies with no party affiliation. It’s no coincidence that there are so many more parties represented in the Dáil than in American legislatures. RCV allows a greater number of views a seat at the table.
Overall, the level of competition in this election was outstanding. Every single constituency in Ireland was competitive. There was not a single seat that one party was guaranteed to win. Even if all of the minor candidates (those who lost their election expenses) are not counted, there were still more than two candidates contesting each seat on average. Voters certainly took advantage of this additional choice as no single party swept the seats in any constituency.
Over-Representation Is Reduced
Now let’s look at how over-representation is affected. To compare with the US results from my previous article, I calculated the difference between the percentages of seats won by Fine Gael and first-preference votes the party received. A graph showing the full comparison is below.
Even with only looking at first-preference votes, the Dáil already has a more proportional representation than most American legislatures. However, this does not take into consideration a huge advantage of RCV; the fact that voters get to rank their choices! If their first-choice candidate is eliminated, their vote transfers to their next choice. Likewise, once a candidate gains enough votes to win a seat their surplus votes are distributed proportionally to the next choice of their voters.
Because of this mechanic, I decided to also look at the percentage of votes the winners finished with. Since there are so many candidates in each constituency, I believe most Irish voters would only rank the candidates they want to win. This is in contrast with the common strategy in America, where some will use their single vote to vote against the worst candidate.
In all constituencies the winners ended up with over 70% of the votes between them. Talk about a mandate, right?
The results of the 2016 Dáil elections show that the theoretical benefits of RCV hold up in practice. There is legitimate competition in all constituencies, the makeup of the Dáil more closely represents the views of the voters, and more voters end up with a deputy who they voted for. Any American politician who wants to do something about improving elections should support changing the system to ranked choice voting. If you agree, find your legislators through https://openstates.org/find_your_legislator/ and contact them about this. Sharing this post on social media is fine and all, but contacting your legislator is a much more effective way to affect change.
