Want to break two-party duopoly? Then you need a good voting system.
Detractors of range voting
often make claims like this:
I think you..exaggerate the importance of the election method in
determining how many viable political parties a country has.
Well, it is hard to exaggerate that
importance. Election methods make all the difference in whether two-party
duopoly ensues in single-winner posts (mayor, governor, president, etc.). Election methods which fail the Favorite Betrayal Criterion (i.e. you vote for your "second
choice" instead of your first choice, to protect yourself from getting a worse choice) are inherently conducive
(usually strongly conducive) to two-party domination. Welcome to Duverger's Law.
Some claim that two-party domination is a
problem intrinsic to single-winner elections; that no voting system can change
that. Yet we know that traditional top-two runoff systems, used in at least 26 countries, have in many cases
proven that claim wrong. And because range voting does
not exhibit an incentive for favorite betrayal, we have every reason to believe
that it will also lead out of two-party duopoly. But even once convinced that a voting method can have this
effect, some don't seem to think it's very important, and say things like:
This is perhaps a pedantic point, but I don't think the goal of our voting system
should be to dismantle the two-party duopoly per se.
or
[Range voting supporters]
also exaggerate the importance of how many competitive parties there are as an indication of how "democratic" a country
is.
Again, this is hard to exaggerate, as it's an extremely
powerful indicator of how good an election system is at turning voter sentiment into the most overall pleasing result
for the electorate. Here's why.
Say we were to create, in n-dimensional political issue space, an
infinite number of political parties, such that for any voter, there would be an ideal party for him. This is the
hypothetical "ideal" democratic situation. In this realm we would have, for instance, some populist party, Q,
which on an axis of fiscal conservatism/socialism (one direction implying support for higher taxes and more social
services, and the other implying lower taxes and services) were to lie at some point P1. Now then, we have
another party, X, whose coordinates in n-dimensional political issue space are identical to Q, except for lying a little
further down toward the conservative end of the fiscal axis, at point P2. Then let us say that with every
party/candidate, there is an associated average "utility" or "preference" score, based on the preferences of the
electorate at any given point in time. Logically then, the most total satisfaction would come to the electorate,
were the party/candidate with the highest average utility score to be in power at any given point in time (breaking
this into terms of office, for obvious sheer pragmatism).
Now because political viewpoints are constantly
changing in a dynamic society, in which new people become adults, and other adults die, and college kids read
Kierkegaard, we must accept the obvious expectable result, that within the
myriad of these infinite parties whose utility scores lie near the maximum, the dynamic shifts in socioeconomic
perspectives, and shifts in any ideologies which could affect voter sentiment
about a given candidate (this could be virtually anything), will produce winners
from different parties in virtually every election. The degree of this effect is limited by the practical extent
to which parties could effectively differentiate themselves in the eyes of voters. But as a practical thought
experiment in this vein, imagine a series of political parties representing the ideologies at a series of points along
the 2-dimensional axis of the Nolan chart, as shown below, and encompassing all ideological space to the respective
boundaries of equidistance between the specified points.
Say we start with a mere
2-by-2 set of points, such that there is a party representing the points around the center of the Republican,
Libertarian, Totalitarian, and Socio-Crat regions. Faced with such a small number of parties, and the fact that
ideological distribution would not favor a gravitation toward the upper-right or lower-right quadrants of this chart,
we could expect to see the standard 2-party duopoly exhibited in countries like the U.S., Australia, Ireland, etc.
But now say we went to a 10-by-10 set of points, such that the ideological "compression" of chart space into
potential political party affiliations was dramatically reduced. That is, the average distance between a voter's
ideological point on the chart, and the closest political party was dramatically reduced. Were we now to
implement an election method which passes the Favorite Betrayal Criterion, and very accurately measures voter
satisfaction (in an analog sense especially), we would obviously expect to see the winning party be different from year
to year, with several near the most popular regions of the chart able to show clear viability by coming in very close,
even if they do not frequently win.
This thought experiment shows in exceeding detail, why we should expect
to see numerous viable parties in a country using a good election method, given any normal human society. Thus, if we don't see a healthy variety of parties, we
know that the election method in use is highly flawed.
Going a little further, a really good voting method, like Range Voting, could actually make parties obsolete;
candidates would instead point to a location on the political map to give a general idea of where they sit. After
all, giving people a general idea, at a glance, of what your core values are, is the primary function of a party in the
first place, if you're using a good voting method.