Approval Voting Is Better Than Plurality Voting, Even In Multi-Winner Races

clay shentrup
3 min readFeb 1, 2016

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There have been some cases where approval voting, which is ideally intended as a single-winner voting system, has been criticized as being unsuitable for multi-winner “at-large” elections, as was adopted in Fargo, ND.

Approval voting used in a multi-winner election works the same way as ‘’Plurality-at-large’’, but allows more votes than winners, which gives the majority even more power to elect all the winners, and reduces the power of ‘’bullet voting’’ to help minority candidates.

The Troubling Record of Approval Voting at Dartmouth, FairVote

Suppose you have the following scenario:

Voters are roughly split into three factions: left, right, and center. There are three candidates from each of those factions (i.e. nine total candidates), and we’re electing three winners.

The critics argue that the outcome should be proportional, such that we elect one winner from each faction. Approval voting will presumably tend to elect all three centrists, which is less representative of the diversity of the electorate.

But note that this still gives an elected body with the same ideological center as the electorate, which is crucial. That should ensure that the legislation produced is “representative”, even if the legislating body itself is comprised of a relatively uniform group of centrists. The center is, after all, a position that is influenced by voters on both the left and the right, and any other political interest group we might consider.

There are then complex tradeoffs to consider here. A proportional body would have members of underrepresented minorities, who could use that as a pulpit from which to lead the conversation on issues that might otherwise receive little attention. However a proportional body might also serve to exacerbate tensions between strong partisans from both the leftist and conservative flanks. A centrist body might be expected to diminish the sense that there are “two Americas”, and lead to more efficient and less partisan policymaking. I don’t intend to resolve this debate here—this is merely food for thought, meant to highlight the inherent ambiguity of proportional vs. non-proportional elections, the former being often treated as an unalloyed good among electoral reform advocates.

Now imagine that instead of at-large (non-proportional) approval voting, we stick with traditional at-large plurality voting, where voters can only select only as many candidates as there are winners. While this is likely to produce a more diverse outcome, it does so quite randomly, via a crude and imprecise mechanism of vote splitting. It is thus conceivable that the ideological center of the elected body would diverge from that of the electorate.

To refer back to our hypothetical three-winner election, you could get a centrist and two leftists for example. More diverse than a uniform body of centrists, but arguably less representative, due to an ideological center that is significantly left of the overall electorate. In extreme cases you might even get all three candidates from one end of the political spectrum, meaning an outcome that’s neither diverse nor representative.

In summary, the concerns about proportional representation are a perfectly reasonable grounds for favoring proportional approval voting over simple at-large approval voting. But I don’t think this favors at-large plurality voting over at-large approval voting. To state this simply:

Proportional approval voting is better than at-large approval voting (is better than at-large plurality voting).

The part in parentheses is my framing as Devil’s advocate. I am actually skeptical that the benefits of proportionality outweigh the problems, but I think this sentence is plausible and reasonable, and deserves consideration as the best compromise position with the critics of at-large (non-proportional) approval voting.

So if you agree, like the vast majority of voting methods researchers, that plurality voting is bad, then please don’t let the perfect be the enemy of the good.

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clay shentrup

advocate of score voting and approval voting. software engineer.