In a plebiscite on 2 June 1946, the Italian people voted (12,700,000 to 10,700,000) to end the constitutional monarchy, which had existed since 1861, and establish a republic. At the same time, a constituent assembly was elected, which proceeded to draft and approve a new constitution; it came into force on 2 January 1948. Under this constitution, as amended, the head of the Italian Republic is the president, who is elected for a seven-year term by an electoral college consisting of both houses of parliament and 58 regional representatives. Elections for a new president must be held 30 days before the end of the presidential term. Presidential powers and duties include nomination of the prime minister, who, in turn, chooses a Council of Ministers (cabinet) with the approval of the president; the power to dissolve parliament, except during the last six months of the presidential term of office; representation of the state on important occasions; ratification of treaties after parliamentary authorization; and the power to grant pardons and commute penalties. Although the constitution limits presidential powers, a strong president can play an important political as well as ceremonial role.
Legislative power is vested in the bicameral parliament, consisting of the Chamber of Deputies and the Senate. Members of the 630-seat lower house, the Chamber of Deputies, must be at least 25 years old and are elected for five-year terms. The 315 elective members of the Senate must be at least 40 years old and are elected for five-year terms. Former presidents of the republic are automatically life senators, and the president may also appoint as life senators persons who have performed meritorious service. Citizens must be at least 25 years of age to vote for senators; otherwise, those over the age of 18 may vote in all other elections.
In August 1993, Italy made significant changes in its electoral system. Three-fourths of the seats in both the Chamber and the Senate would be filled by simple majority voting. The remainder would be allocated by proportional representation to those parties securing at least 4% of the vote. The first elections under the new system in March 1994 resulted in a simplification of electoral alliances and brought a center-right government to power. Silvio Berlusconi, founder of the "Go Italy" (Forza Italia) movement, emerged as prime minister.
The constitution gives the people the right to hold referenda to abrogate laws passed by the parliament; a referendum requires at least 500,000 signatures. Four referenda had been held by 1987 (against the legalization of divorce in 1974, against increased police powers and state financing of the political parties in 1978, and against government cuts in wage indexation in 1985), and in all of them, the voters approved the parliamentary decisions.
On 21 May 2000, Italian voters were asked to decide on electoral reform by increasing the number of lower house seats filled on the basis of a non-proportional system to 100%, effectively scrapping the last remaining element of pure proportional representation. The referendum needed to secure a quorum of 50% of the electorate to gain validity. The final turnout of 32% was much lower than expected and was an alarming sign of voter fatigue and popular disaffection.