Benefits of Proportional Representation
The fundamental argument for proportional representation is that, to the extent possible, each voter should have a voice in their representative bodies: national and state legislatures, local boards and councils.
More voters are represented
In single-winner districts, “competitiveness” is generally considered to be a virtue—we prefer districts where elections are not foregone conclusions. But we also observe that the more competitive a single-seat district, the more voters (as many as half, and maybe more) are on the losing side, unable to elect their own representative. With proportional representation, on the other hand, a group of voters need not make up a majority in order to elect a representative. Depending on the number of seats, the threshold for representation can easily be 10–20% of the voters, or less.
PR encourages candidate quality and diversity
When single-seat districts are uncompetitive, the minority party (or other voting group) finds it difficult to recruit high-quality candidates capable of running a competitive campaign, because the outcome of the election is a foregone conclusion. Consequently, campaigns become perfunctory or even non-existent. With PR, on the other hand, a diverse range of candidates is motivated to campaign vigorously, precisely because the election is never a complete “lock” for one group or the other.
Representation of diverse views within parties
Voters within our major parties have a fairly wide range of views on many issues. A PR system has the ability to represent that range of view within a party or other voting group, as well as positions across groups or parties. So a conservative Democrat in San Francisco can help elect a conservative Democrat to Congress, while both conservative and moderate Republicans (not to mention Democrats) can elect representatives in Texas.
This is accomplished directly by the voters under STV. With list PR, the list creators are motivated to make their lists diverse because voters ultimately have the power to create new parties if their views are excluded from the lists.
Representation of minority groups and parties
While PR is often credited with making representation available to third parties, what’s often overlooked is that it also enables representation of major parties when they’re a local minority. For example, all of the dozen or so of the San Francisco Bay Area’s congressional districts have Democratic representatives. But registered Democrats outnumber Republicans by “only” 2:1 or 3:1 in this area. That’s enough to make it effectively impossible to elect a Republican representative. But under a PR system, Republican voters would elect 3–4 out of the 12 Bay Area representatives. Conversely, Democratic voters would be able to elect representatives in the heavily Republican districts of California’s Central Valley. The statewide party balance would likely not change very much, but virtually every Republican and Democratic voter would have a direct voice in electing their own representatives.
Many voting-rights complaints center around the problems of plurality at-large elections. In these elections, voters typically cast as many votes as there are seats, and the top vote-getters are the winners. This is a “plurality-take-all” system, in which a plurality of voters has the power to elect every seat. Consequently, a city or school district might have a large minority population who can be completely excluded from representation, if voting is along ethnic or racial lines.
The most common “fix” proposed in such a situation is the imposition of district elections. For example, a city with seven city council seats is divided into seven single-member districts. This solution suffers from at least three major defects. The first is that it relies on gerrymandering, or artful drawing of district boundaries, in order to guarantee that “majority-minority” districts are created. The second is this approach relies on sufficient segregation that such districts can be created. And finally, as with all single-member districts, many, perhaps even most voters, end up without representation.
The STV PR solution retains a single multi-seat district, but fills the seats proportionally. Minorities are empowered to elect representatives in proportion to their numbers, if they desire, or to choose to vote for candidates based on other priorities. Nearly all voters are able to contribute to the election of a representative that they approve of.
In many states, elected representatives are responsible for drawing their own district boundaries. This leads to abuses, most notably gerrymandering to create “safe” districts for a party or a particular representative. These abuses should of course be corrected. However, when states have reformed their redistricting procedure by putting it in the hands of neutral parties, we find that under the reformed system, incumbents are just as likely to be re-elected, and nearly as many seats are “safe” (non-competitive) as under the old gerrymandered districting.
This should not be a surprise, since voters of a feather tend to live together. A congressional district in the San Francisco Bay Area will safely elect Democrats regardless of how its lines are drawn.
PR solves this problem by empowering all significant groups of voters to choose their own representation. If the SF Bay Area has 40% Republicans and Republican-leaning independents, those voters can elect 40% of the Bay Area seats, and conversely, a proportional number of Democrats will be elected from California’s Republican-leaning Central Valley. Not only are voters in a political minority able to elect their own representatives, but the advantages of (and motivations for) gerrymandering simply disappear.