Duverger's Law and the Philippines

Meghan Maddock

Blog 7: Duverger’s Law

            The electoral system of the Philippines’ House of Representatives is a hybrid structure, meaning that its formula is neither completely single member district plurality (hereafter referred to as SMDP), nor is it completely proportional representation (hereafter referred to as PR). Rather, 228 of the House of Representatives’ 280 seats are filled by SMDP “first-past-the-post” electoral rules, meaning that the country is divided into districts, in each of which one seat is won by the candidate with the plurality of votes, while the remaining 52 seats are filled according to PR rules (“PHILIPPINES”). The election for the SMDP seats of the House is held with an open and preferential list structure, meaning that voters vote for their preferred candidate. The formula of the Philippines’ House of Representatives is known as  “parallel voting”, meaning that there are, in effect, two separate elections for one chamber and neither election impacts the other (“Parallel Voting”). There are no thresholds for the SMDP seats.

The 52 remaining seats are filled using PR by party nominees from minority parties. They are elected through a closed nonpreferential list, meaning that voters vote for their preferred party, not for a specific candidate (“Sectoral Representation”). A single minority party cannot be given more than three seats and there is a threshold of two percent, meaning that a party must have at least two percent of the vote before it can receive a seat. (“PHILIPPINES”).  There are 228 legislative districts for a 280 seat House of Representatives, giving the Philippines’ House of Representatives an average district magnitude of 1.2. The portion elected by SMDP has a district magnitude of one, while the portion elected by PR has a district magnitude of 0.2 (“House of Representatives”).

The effective number of political parties is calculated by taking the inverse of the sum of the squared proportions that each party has in the legislature (Hawkins). As of 2010, the Lakas-Kampi Party is in control of 36.93 percent of the Philippines House of Representatives, while the Liberal Party has 15.38 percent, the Nacionalista Party has 9.08 percent, the PMP Party has 1.40 percent, and the NPC Party has 10.14 percent (“Politics of the Philippines”). The sum of the squared values of those proportions is 0.1785, the inverse of which is 5.6. In the Philippines, the effective number of political parties is 5.6.

The House of Representatives of the Philippines seems to support Duverger’s Law, which states that SMDP electoral systems will tend to foster a system of only two parties, while PR electoral systems are likely to have more than two parties (Hawkins). The Philippines’ House of Representatives employs a hybrid system, so it does not fall neatly into either of Duverger’s groups. However, the number of effective political parties being 5.6 indicates that the ability of smaller parties to gain seats through the allotted PR spots has encouraged the growth of multiple parties. Though only twenty percent of the seats are under the PR system, their presence has helped create a multiparty system. Overall, the complicated case of the Philippines’ House of Representatives supports Duverger’s Law.

           

Works Cited

Hawkins, Kirk. "Political Parties." PL SC 150. Joseph F Smith Building, Provo. 29 Oct. 2012. Lecture.

"House of Representatives of the Philippines." Wikipedia. Wikimedia Foundation, 24 Oct. 2012. Web. 02 Nov. 2012.

"Parallel Voting." Wikipedia. Wikimedia Foundation, 19 Oct. 2012. Web. 02 Nov. 2012.

"PHILIPPINES Kapulungan Ng Mga Kinatawan (House of Representatives): Electoral System." IPU PARLINE Database. Inter-Parliamentary Union, 24 Jan. 2012. Web. 30 Oct. 2012.

"Politics of the Philippines." Wikipedia. Wikimedia Foundation, 22 Oct. 2012. Web. 30 Oct. 2012.

"Sectoral Representation in the House of Representatives of the Philippines." Wikipedia. Wikimedia Foundation, 26 Oct. 2012. Web. 02 Nov. 2012.