Published on September 25, 2017.

Overview of Japanese Politics

1. Prime Minister and the Cabinet

In Japan, Prime Minister (PM) is elected from Lower House members and appointed by both Houses. In practice, the head of a leading ruling party usually serves as PM. One can serve a 4-year term for as many times as he/she is elected. PM appoints or disappoints ministers. The majority of cabinet ministers have to be members of the parliament. With ministers heading ministries, the cabinet is an executor of the manifesto or promised policies because the cabinet can propose matters to the Diet (approximately 80% of the laws that pass the diet originates with the cabinet).

Mr. Shinzo Abe has been serving as Japan's PM since December 26, 2012. He is already the 3rd longest serving PM in Japan after the WWII. Shigeru Yoshida who signed the Peace Treaty with Allied Powers in 1951 is currently the 2nd longest, having served for a little over 6 years between 1948 to 1954. Eisaku Sato who accomplished the return of Okinawa from the US is the longest, having served for little under 8 years between 1964 to 1972.  

2. Diet

Japan's Diet consists of The House of Representatives and The House of Councilors. The former is often called "Lower House" and the latter "Upper House". Any legal amendment/ proposals must pass both houses by majority vote to be effective. 465 Representatives for Lower House shall be elected every 4 years, while half of 242 Councilors for Upper House shall be elected every 3 years to serve 6-year terms. Lower House used to have 475 seats, but the number has been reduced to 465 in 2017. For the Representatives, the next election is to be held within 4 years from the latest election held on October 22, 2017. Prime Minister cannot dissolve the Upper House and the next Upper House election will be held on July 2019.

Under the leadership of Prime Minister Abe, the current ruling coalition have been winning the clear majority of both Lower House (in 2012, in 2014 and in 2017) and Upper House (in 2013 and again in 2016). See below table for the by-party composition of Upper and Lower House. The definition of abbreviation is given in the next section.

Strength of political parties in Upper and Lower Houses

3. Political Parties

Since 2007, two parties, LDP and DPJ, have been the main forces determining political landscape in Japan. Major political parties in Japan are as follows:

  • Liberal Democratic Party (LDP)
    A long-standing political party established in 1955. It has conservative and pro-business tendencies. The party has been ruling Japan for most of the period between 1955 and 2009 except for a brief period between 1993-94 and 2009-2012. It is currently the leading ruling party.  

  • Komei 
    Komei party was originally established in 1961 as a political arm of a religious group, Soka Gakkai. Soka Gakkai is a faith based on Buddhism. Since 1999, the party tended to form an alliance with LDP and it is currently a junior ruling partner to LDP. The party has a support base among the elder population.

  • Democratic Party of Japan (DPJ)
    DPJ was established in 1998 as a "center" party by a mixture of political groups including former members of LDP, centrists as well as former socialists. The party has a support base among labor unions, but it also seeks to extend its support in the rural areas as well. The party was the leading ruling party between 2009 to 2012. Since then, the party has been suffering constant internal strife. In September 2017, its newly elected leader, Seiji Maehara, proposed to merge the party with the Party of Hope, only to see the party splinter as a result. As of October 2017, it is yet uncertain if DPJ would be disbanded. 

  • Constitutional Democratic Party (CDP)
    Hastily formed 3 weeks in advance to the October 2017 Lower House election, the party tripled its seats to become the largest opposition party in the Lower House. Led by Yukio Edano, the party has a center-left tendency and fought the election with a pro-pacifist constitution agenda, allied with communist (JCP)  and socialists. With the demise of DPJ, the former leading opposition party, CDP is the leading contender to replace it.
  • Japan Restoration Party (JRP)
    The party pursues a liberal, market-based economic policies while having a nationalistic and hawkish tendency in security policy areas. Currently, the party is headed by Ichiro Matsui who is a governor of Osaka prefecture.

  • Japan Communist Party (JCP)
    Established in 1922, Japan Communist Party is one of the oldest existing political party in Japan. During the cold war, the party and its supporters have often been politically prosecuted as potential allies to socialist block. While such perception has diminished in recent years, most political parties tend to still avoid being perceived as an ally to JCP. Its support base is in the urban areas. In the 2014 lower house election, JCP was perceived as one of the only opposition party offering a coherent set of economic policies and doubled its seats in the lower house. In 2017, it allied with the newly formed CDP to help it gain seats in single-seat constituents. While the alliance worked for CDP, JCP suffered a heavy loss.  

  • Party of Hope
    Hastily formed in September 2017, the party is led by Yuriko Koike, the governor of Tokyo. The senior members of the parties are breakaways from LDP and DPJ. The party does not have a strong unifying set of policies aside from a vague “reform” theme. After a brief moment of inspiration, the party quickly lost its momentum and suffered a loss in the October 2017 Lower House election.   

    Political Map of Japanese political parties and leaders