From 1953 to 1963, Northern Rhodesia was a protectorate under the jurisdiction of the British crown, within the Federation of Rhodesia and Nyasaland. On 24 October 1964, it became an independent republic. The constitution of January 1964 was amended in 1968 and in 1972, when it was officially announced that Zambia would become a one-party "participatory democracy," with the sole party the ruling United National Independence Party. A new constitution was drafted and received presidential assent in August 1973.
Under the 1973 constitution, the president of the Republic of Zambia was head of state, commander-in-chief of the armed forces, and president of the UNIP. Once chosen by the ruling party, the president had to be confirmed by a majority of the electorate, but there was no limitation on the length of the president's tenure in office. The prime minister was the leader of government business and an ex officio member of the UNIP Central Committee. As provided in the constitution, the Central Committee consisted of not more than 25 members, 20 to be elected at the party's general conference held every 5 years, and 3 to be nominated by the president, who was also a member. Cabinet decisions were subordinate to those of the UNIP Central Committee. The parliament consisted of the president and a National Assembly of 125 elected members, but all Assembly members had to be UNIP members, and their candidacy had to be approved by the party's Central Committee. The constitution also provided for a House of Chiefs of 27 members. A Bill of Rights guaranteed the fundamental freedom and rights of the individual, but if at any time the president felt the security of the state threatened, he had the power to proclaim a state of emergency. Indeed, Zambians lived under a state of emergency for 27 years.
In August 1991, a new constitution was promulgated. The president is now elected directly by universal suffrage and may serve a maximum of two five-year terms. The National Assembly has 150 directly elected members with up to eight appointed by the president, also for five-year terms. Since 2 January 2002, President Levy Mwanawasa has served as head of state with Vice President Enoch Kavindele (since 4 May 2001). The next elections were scheduled for 2006.