Proportional Representation

The System

The party list vote is the most widely used form of proportional representation, and the most frequently used electoral system in the world, currently employed in about 70 countries. Each party presents a list of candidates, and the voter chooses from among these lists. The total vote for each party determines the number of its candidates who get elected. For example, in a 100-member legislature, a party receiving 10 percent of the vote will be entitled to 10 seats. In a closed party list system, these individuals will be the top 10 candidates on the list (the order on the list is decided by the party leaders). In an open party list system, voters can express their preference for a specific candidate, but these votes will first be added up to give a total party vote. This total will determine how many seats a party will get; for example, the 10 individuals who are elected are the top 10 vote getters.

By definition, proportional representation requires multi-member electoral districts, and the number of representatives elected in a district is referred to as district magnitude. This number ranges from Chile's two-member districts to Ukraine's nationwide, 450-member district. In the latter case, the whole country is treated as a unique district for the purpose of electing the members of its legislature. Most countries want to retain some degree of local representation, thus the country is divided into a set of multi-member districts, and seats are allocated within each district. There is a tradeoff between proportionality, on the one hand, and the closeness of the relationship between representatives and constituents on the other. In a case such as Chile, with only two members elected within each district, the relationship is much closer than in Ukraine, and resembles the constituents-representative link in a single-member district system as in the United States. However, this comes at a heavy price for proportionality: a party must win at least one-third of the total vote to be guaranteed a seat. Thus, smaller parties are essentially excluded from competition in such a system.

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