Duverger's Law and Poland

Duverger's Law and Poland

By Jason Andersen

 How political parties come into power or even emerge as a political power depends greatly on the electoral rules of the country. Countries technically may have scores of political parties however only a handful, if even that, will be represented in a countries elected government. Obviously, the parties with the most votes are the ones represented in government; however, the electoral rules of the country tend to determine how many effective parties there are.  The main question is if a country’s electoral rules are based on proportional representation or single-member-district-plurality, as far as determining the effective number of parties. Duverger’s law mathematically demonstrates how single-member-district-plurality rules tend to lend to just two effective parties while proportional representation rules tend to lend to a greater number of effective parties.

The example of Poland highlights how Duverger’s law holds true and is a classic example of a proportional representation state. In Poland’s most recent 2011 election, six political parties made it on the Polish ballots (Inter-Parliamentary Union, 2011). Poland does have a threshold limit of 5% of the total votes cast for party list and 8% for a coalition list, though national minorities' lists are exempt from thresholds requirements (Inter-Parliamentary Union, 2011). However, just from looking at the ballot results and total seats won, one would assume that there would be three effective parties. Civic Platform party won 45% of the seats, Law and Justice won 34%, Palikot's Movement won 9%, and the Polish People's Party and the Democratic Left Alliance each won 6% of the vote (Inter-Parliamentary Union, 2011).  Duverger’s law states that a countries total number of effective parties can be determined by calculating the inverse of the sum of the proportion of seats won squared by each parties, or Neff=1/∑(p2). As shown in the table below, when you run the election results through Duverger’s formula, Duverger’s law shows that Poland has approximately three effective parties. 

Parties	Seats	Proportion of Seats	P2
Civic Platform (PO)	207	45%	0.2025
Law and Justice (PiS)	157	34%	0.116488658
Palikot Movement (RP)	40	9%	0.007561437
Polish Peasant Party (PSL)	28	6%	0.003705104
Democratic Left Alliance (SLD)	27	6%	0.00344518
German Minority	1	0%	4.7259E-06
Total Seats	460	Number of Effective Parties	2.996657792

                As now shown, Duverger’s law hold true in that Duverger’s formula reflects the number of effective parties in Poland. As one could surmise, Poland runs off proportional representation rules. As far as how proportional representation works in Poland, Poland is broken up into forty-one constituencies in which each constituency elects seven to nineteen of the seats in the Sejm, this is known as the country’s district magnitude (National Election Commission, 2007).  The actual district magnitude determined much like the United States and the House of Representatives in that it is based on population with a fixed amount of seats, 460.  The formula Poland uses to actual disperse the seats based on the results of the election is known as the modified Saint-Lague method (Inter-Parliamentary Union, 2011). Unlike some countries, which use a list-method or a combination of methods, in Poland candidates are elected directly in an open or preferential method (Inter-Parliamentary Union, 2011). The only stipulation is that on the ballot for the Polish Sejm at least 35% of the candidates have to be women and at least 35% of the candidates have to be men (Inter-Parliamentary Union, 2011). Currently in the Sejm 23.91% are women (Inter-Parliamentary Union, 2011).

Bibliography

Inter-Parliamentary Union. (2011). Poland - Sejm. Retrieved November 1, 2012, from PARLINE database: http://www.ipu.org/parline-e/reports/2255_E.htm

National Election Commission. (2007, October 27). Election to the Sejm. Retrieved November 1, 2012, from Electoral Constituencies: http://wybory2007.pkw.gov.pl/SJM/EN/KOMITETY/0.htm