Japan’s electoral system is unique; combining both single-member-district
plurality (SMDP) and proportional representation (PR) electoral rules. The
House of Representatives apportions 300 seats using SMDP and 180 seats using PR1.
So do they still follow Duverger’s Law? Duverger’s Law states: “the effective
number of parties in any electoral district is a function of the electoral
rules.2” Yes Japan does follow this law, by combining aspects of
each system, both types of electoral rules produce the effect predicted by
Duverger’s Law. To prove this, we will examine the effective number of parties,
and electoral rules of the House of Representatives of Japan.
The
effective number of parties that results from SMDP is a two-party system, while
PR supports a multiparty system. Since the majority of seats (300/480=62.5%)
are apportioned using SMDP, we will expect Japan to lean more towards a
two-party system. The effective number of parties is determined by the
following formula2: (Effective number of Parties) = 1/∑p2.
Using the electoral results of 2009, The Democratic Party received 308 seats,
the Liberal Democratic Party 119 seats, the New Komeito Party 21 seats, and
other parties 32 seats1. The proportion of the seats “p” for the
parties is: 0.642, 0.248, 0.044, and 0.066 respectively. Thus p2 is:
0.412, 0.062, 0.002, and 0.004 respectively. So 1/∑p2
= 1/(0.412+0.062+0.002+0.004) = 1/0.48 = 2.08. Therefore the number of
effective parties in Japan is 2.08, which means there are two major parties,
with a few minor parties. Since the majority of seats go towards single-seat
constituencies, we would expect Japan to have two parties.
However,
while the number of effective parties is significant, it is determined by the
electoral rules, which tell us more about the electoral district. Japan
operates under a hybrid system, where 300 of the seats are apportioned using
single-member-district plurality and 180 through proportional representation as
stated earlier. The single-member-district seats are decided by plurality to
local constituencies, while the seats won from proportional representation are
determined by the D’Hondt method per district. The district magnitude of Japan
ranges between 6-29 seats over the 11 districts, with Shikoku at 6 and Kinki at
293. The district magnitude is high because they use proportional
representation, so the country is split into different districts and allotted a
certain number of seats. The list structure of Japan is similar to that of
Germany, where they have two ballots, one which directly elects a local
constituent while the other votes for a party, which is distributed votes by the
D’Hondt method1. The proportional votes use a closed list, where the
party elects from their list, rather than giving the voters say on which
candidates should be on the list, as in an open list system4. Japan
does not have a threshold for the House of Representatives5.
Therefore,
we can see that Duverger's Law is followed in Japan where it applies the
most. As in they have two parties when the majority of seats are won by SMDP,
but they also have a fairly high district magnitude because they also apportion
seats by PR. So we can see that the effective number of parties is determined
and changed by the electoral rules in Japan.
Works Cited
1.
"Elections in Japan." Wikipedia. Wikimedia Foundation, 11 Jan. 2012. Web. 01 Nov. 2012.
2.
Hawkins, Kirk. “Electoral Systems.” Lecture.
October 31, 2012
3.
"List of Districts of the House of
Representatives of Japan." Wikipedia. Wikimedia Foundation, 10 Dec. 2012. Web. 01 Nov.
2012.
4.
"D'Hondt Method." Wikipedia. Wikimedia Foundation, 29 Oct. 2012. Web. 01 Nov. 2012.
5.
"Electoral Reform in Japan?" Electoral Reform in Japan? N.p.,
1995. Web. 01 Nov. 2012.
The explanation of how Japan is a hybrid was good. I think an explanation of d'hondt's method would have helped make things even more clear.
ReplyDeleteI liked how you spelled out your methodology, the formula was clear and it was easy to see how you got your results.
ReplyDeleteI find it interesting that Japan does not rate higher on the effective number of systems. There is clearly a two party system here, which I would think according to Duverger's law would not be the case. If they have such a hybrid system then I would think there would be at least a leaning towards an additional party. But I suppose this is not the case, and I wonder what the cause of this could be.
ReplyDeleteI agree with everyone else on their comments, but I also love how you used your title to help explain what you were trying to show.
ReplyDeletegood job on explaining the complex system of japan
ReplyDelete