Members of both houses are elected by universal adult suffrage. As of the last general election, the membership of the House of Representatives was reduced from 500 to 480 (Public Offices Election Law, revised February 2000). The four-year term is unchanged. The House of Councillors membership is 242, with half of its members elected every third year for a six-year term.
(1)Election to the House of RepresentativesThe first House of Representatives Election Law in 1889 set strict voting qualifications. The minimum age requirement for voters was 25 and that for candidates 30, and an additional qualification restricted the franchise to males who paid 15 yen or more per annum in direct national tax. Of the total population of 40,000,000 at that time, only 450,000 people were entitled to vote. The total membership of the House of Representatives was 300 - 214 from one-member and 86 from two-member constituencies.
The 1900 election statute provided for an increase of membership to 369 and the introduction of large constituencies, whereby each of the 47 prefectures constituted one district returning from three to 13 members and each of the 48 largest cities constituted one district returning from one to 11 members. The minimum qualification regarding the payment of tax was reduced to 10 yen per annum. Later, minor reforms were undertaken with respect to total membership, the size of electoral districts, tax requirements, and other matters.
In 1925, universal adult male suffrage was established, extending the franchise to all men 25 years of age and over, and the tax qualification was eliminated, with the result that the number of voters increased to about 12,000,000. The 1925 election statute provided for a system of medium-size, multiple-seat constituencies, each district returning from three to five members.
After World War II, the Election Law was revised again, in 1945, lowering the minimum age for voters to 20 and that for candidates to 25; at the same time, the right to vote and to run as a candidate was granted for the first time to women. Thus, in the general election of 1946, 39 women were elected to the House of Representatives.
The present election system is a combination of the single-seat constituency system and proportional representation. Under the system, out of 480 Members, 300 are elected from single-seat constituencies, and remaining 180 by proportional representation in which the nation is divided into 11 electoral blocs which according to size return between six and 30 Members. Voters cast two ballots: first, one for an individual candidate in the single-seat consitituency, and second, one for a political party in the proportional representation election.
The combined election system was adopted and went into effect to replace the long-standing multi-seat medium-sized constituency election system, which was abolished in January 1994 by a revision of the Public Offices Election Law. This election system was first used in the 41st general election for the members of the House of Representatives held in October 1996 in which 300 were elected from single-seat constituencies and 200 by proportional representation, and again in the 42nd general election held in June 2000 after reducing the number of Members elected by proportional representation from 200 to 180 by another revision of the Public Offices Election Law.
(2)Election to the House of Councillors
Ninety-six of the 242 Members of the House of Councillors are elected by proportional representation from a single nationwide electoral district. The remaining 146 are elected in 47 prefectural constituencies, each returning two to ten members. Voters cast two ballots - one for a political party or a candidate in proportional representation and one for an individual candidate in a constituency.
The minimum age requirement to be a candidate for the House of Councillors is 30, and that for voters is 20.It should be noted that the House of Representatives can be dissolved, whereas the House of Councillors is not subject to dissolution. When the House of Representatives is dissolved, the House of Councillors closes its session at the same time. However, the Cabinet may, in time of national emergency, convoke an emergency session of the House of Councillors. Measures taken at such a session are provisional and become null and void unless the consent of the House of Representatives is obtained within 10 days of the opening of the next session of the Diet.