Lesson 4 of 8
In Progress

Why Plurality Is Killing Us

Roy Minet October 17, 2022

The Plurality voting method solicits just one datum from each voter; that datum is which candidate the voter thinks is the best one.  The votes are totaled and the candidate receiving the most votes is designated the winner.  Plurality is the most widely used voting method and the simplest (it’s too simple); it also is the worst.

About the time of the American Revolution, two French scholars, Nicolas de Condorcet and Jean-Charles de Borda pointed out some of the serious problems with Plurality.  More recently, it has been realized that Plurality is even worse than Condorcet and Borda thought.  They proposed voting methods of their own that they theorized were superior. This kicked off a 250-year-long debate over various alternative voting methods.

The most glaringly obvious defect with Plurality is that a candidate can win with less than a majority of the votes whenever there are more than two candidates.  We have learned that sometimes even a majority of votes is not a strong enough criterion to identify the winner which will maximize voter satisfaction, so Plurality sometimes elects an incorrect winner even in two-candidate races.

Plurality does not collect enough information from voters to enable it to reliably identify the correct winner.  Worse, the meager information it does collect is very often bogus.  That is caused when the extremely powerful vote-for-the-lesser-evil pressure that Plurality engenders causes voters to vote for a candidate they do not like, in order to prevent a win by a candidate they like even less.  Thus, Plurality is highly susceptible to strategic voting.

What is perhaps most surprising, not to mention disturbing, is that Plurality can elect a candidate that the majority of voters dislike!  In the 2016 U.S. presidential election, polling data by Pew Research just ahead of that election indicated that Donald J. Trump had only 11% solid support from likely voters, while in fact, a majority of voters did not like him.  Hillary R. Clinton was microscopically better with 12% solid support, but a majority of voters also disliked her.  Trump was nevertheless elected.  The 2020 presidential election appears to have duplicated this feat and elected Joe Biden even though a majority of voters dislike him as well as disliking his opponent, Donald Trump.

In recent years, it has been recognized that Plurality voting actually is exacerbating the extreme polarization we are experiencing, both in politics and spilling out into our society.  Once polarization starts, it’s bound to get worse.  Here is how that works.

Most major elections are decided by less than 5 or 6 percentage points, frequently less than 2 percentage points.  Since voter turnout is only in the 60% range, political parties believe (perhaps correctly) that increasing the turnout of their “base” voters is the best strategy to gain that few additional percentage points needed to secure a win.  As polarization increases, it’s harder and harder to attract voters from the opposite camp.  Thus, the parties nominate the more “extreme” (and polarizing) candidates that will motivate their base voters to get out and vote.  Base voters also are strongly motivated to turn out because of their mortal fear of a win by the candidate at the opposite extreme.  It would be hard to create a more divisive situation if that were the goal!

In a nutshell, Plurality not only does a terrible job of enabling voters to choose the candidate that maximizes their satisfaction, but it also encourages the nomination of divisive candidates over ones which would result in higher voter satisfaction. There is no way voters can elect great candidates if they aren’t even on the ballot.  Over time, Plurality strongly favors the formation of two polarizing extremes virtually to the exclusion of other candidates, even if or when they do appear on the ballot and regardless as to whether or not they are better candidates.

It should be abundantly clear that Plurality is doing us grave harm and needs to be replaced as soon as possible.  A few jurisdictions have tried voting methods that can only make a small improvement.  The evidence so far does not indicate much, if any, actual improvement.  That is because a major, qualitative improvement is needed; that can only be provided by a very much better voting method which is able to decisively fix a number of the problems with Plurality.

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