The American two party system is unique, but few would regard it as exceptional. Several democracies have two dominant parties or blocs of parties, including the United Kingdom, from whom we originally adopted our electoral system, but ours is the only true two party system. Over the last few decades, this has resulted in a system characterized by partisan polarization.

Partisan polarization is especially acute in California, where the average Democratic Assembly member is far more liberal, and the average Republican far more conservative, than the median California voter. As we move into the 2010 general elections, approval ratings of the state legislature and governor are at historic lows, and Californians have an increasingly dim view of the future. More generally, we have witnessed a consistent decline in political support for the dominant political parties and political leadership nationwide over the last 40 years. The good news, if you can call it that, is that we are not alone: political support is declining in many of the world's older democracies, for reasons that are not directly related to political parties. The bad news is that our particular two party system exacerbates tensions between citizens and government.

We can, and should, do better for our citizens. One alternative is to allow more political parties to compete for leadership. Multi-party systems outperform two party systems on a number of indicators commonly used to measure the quality of democracy.

Let's first consider the input side of democracy, which focuses on electoral participation and public attitudes about system performance.

Voter turnout is higher in countries with more parties. Democracies that have few parties often use single member districts in legislative elections. Indeed, the major consequence of using single member districts is fewer competitive parties, because only one party can win in a given district. Consider the congressional districts in California. Regardless of how competitive a district is, there can only be one winning party. It is difficult for small parties to survive under these conditions. Knowing this, few voters are willing to vote for third parties, even if those parties match their policy preferences better than the major parties.

Without parties that closely match their policy preferences, citizens are less motivated to show up at the polls. Moreover, even in single-member districts that are gerrymandered so one party is virtually guaranteed victory, there is a substantial proportion of voters whose votes are wasted on the opposition party. In my Congressional district on the Central Coast, the Republican Party typically receives 35-40% of the vote, but 0% of the representation. Why bother to turn out when the outcome is predetermined?

In multi-party PR systems, even minor party supporters get representation, so their votes are not wasted. Not only are there fewer real losers in multi-party systems, when we compare them to losers in first-past-the-post (FPTP) systems, they are, on average, more satisfied with the performance of government. Given that losers are more satisfied with government in multi-party systems, and that there are fewer losers overall, we see why political satisfaction tends to be higher in multi-party systems.

Let's also consider performance. Don't numerous parties competing for control make governing more difficult and government less efficient? A number of scholars, among them Arend Lijphart and G. Bingham Powell, have developed an impressive body of research over many years that demonstrate the effectiveness of multi-party systems.

For one, policy outcomes in multi-party systems tend to more closely match the preferences of the median voter than policies in U.S. style FPTP. We can look back to our own James Madison, one of the greatest American political scientists, for insight as to why this is the case. It was he who, in Federalist 10, suggested that by bringing in a greater variety of interests, factions would have to bargain and compromise, moderating policy outcomes and protecting the rights of vulnerable minorities. Usually no single party has a governing majority in a multi-party system, and as a result, legislative decisions are the product of coalition governments.

In addition to being more closely aligned with the average voters' interests, countries using PR exhibit equal if not superior performance on a number of policy outcomes compared to FPTP: U.S. per capita GDP is among the highest in the world, but many of the world's wealthiest countries have large multi-party systems (Belgium, Germany, Norway, Switzerland), and they all have lower income inequality; developmental statistics like infant mortality, literacy, and education tend to be higher in multi-party systems; these same countries have higher percentages of women and minorities in government, another indicator of strong civil rights and civil liberties.

Our two parties do not fare well against multi-party systems on a number of comparative democratic standards, and the effects are starting to show. Fewer Americans are identifying with either Republicans or Democrats, and more independents are running for office. While minor party support is still comparatively low, when one considers the success of Ross Perot, Jesse Ventura, and centrists like Arnold Schwarzenegger, there is evidence of cracks in the system.

If California or the U.S. as a whole were to adopt a more permissive electoral system, we would be following the lead of a number of other democracies. Since 1993, seven countries changed from FPTP to mixed systems that incorporate some proportionality, and five others moved from FPTP to full PR. The worldwide trend is clearly moving in the direction of proportional representation. This brief review helps to explain why: multi-party democracy provides a more accurate rendering of public interests in electoral competition. Legislative outcomes in multi-party systems reflect the deliberation and compromise necessary for building majority coalitions among diverse sets of actors. These developments reflect an adaptive evolution and expansion of democratic values across the globe.