Party System Institutionalization (PSI)
This week’s podcast throws around quite a bit of political science jargon. One of the terms we discuss is party system institutionalization (PSI). It’s a bit confusing because it refers to the health of the party system rather than any individual political party. The United States is a country with high PSI, because it’s two parties remain consistently competitive. On the other hand, Peru is a country where few political parties survive subsequent elections. Most political scientists consider it a country with low PSI.
Scott Mainwaring among others argue PSI contributes to the consolidation of democracy. Political environments with low PSI gravitate towards populist politicians who rely on charisma rather than platforms. Moreover, many politicians avoid accountability from voters as they shift allegiances between different parties from one election to another. Still, it’s difficult to measure PSI. If the party system is relatively stable, a fragmented party system can institutionalize. Meanwhile, the dominance of a single political party can signal low PSI, because the opposition fails to consolidate into consistent parties.
At the same time, party systems might behave differently at different stages of democratization. Allen Hicken, Samuel Baltz, and Fabricio Vasselai “find no support for the claim that party system fragmentation decreases the level of democracy. Rather, our results suggest that the centralization of power is a greater threat to overall democratic stability.” They use party system fragmentation as a measure for PSI. However, single party dominance can also signal weak PSI. So, their findings do not necessarily dispute the more sophisticated concept. Yet they do show how different forms of weak PSI affect democracy. Moreover, they note their findings relate more to countries with lower levels of democracy. Overall, they “found some support for the positive role of party institutionalization in supporting democracy.”