Under the constitution of 18 April 1980, independent Zimbabwe had a bicameral parliament consisting of a house of assembly with 100 members, 20 of whom were elected by white voters, and 80 by persons on the common voters' roll, which included all voters except whites. The upper house, or senate, had 40 members, 14 of whom were chosen by the 80 assembly members elected from the common roll, 10 by the 20 white assembly members, 10 by the council of chiefs, and 6 nominated by the president on the advice of the prime minister. The racial basis of parliament could not be amended until 1987 unless by unanimous vote of parliament; amendment afterward needed only a 70% vote of the assembly. During the first 10 years of independence, the declaration of rights in the constitution could be amended only by a unanimous vote of the assembly; amendment of other clauses required a 70% majority. In August 1987, as soon as the constitution allowed, the separate representation for whites in parliament was abolished and the 20 seats were temporarily filled by representatives selected by the other 80 members.
After the 1990 elections, the two houses of parliament were merged into a single chamber of 150 members—120 elected by popular vote serving for five years, 10 traditional chiefs, eight provincial governors, and 12 members appointed by the president. A constitutional change created an executive presidency and abolished the office of prime minister. ZANU leader Robert Mugabe assumed the presidency on 1 December 1987. Amidst controversy, he was reelected in March 1990, March 1996, and March 2002.
There is universal suffrage from age 18. The next presidential elections were scheduled for March 2006 and legislative elections were scheduled for June 2005.