According to the 1980 constitution—the nation's first—the Republic of Cape Verde was a one-party state, under the guidance of the PAIGC; this party was replaced by the African Party for the Independence of Cape Verde (Partido Africano da Indepêndencia do Cabo Verde—PAICV) in January 1981, after the coup in Guinea-Bissau. The secretary-general of the PAICV and president of the republic, Aristides Maria Pereira, was elected to national office by the People's Assembly, the national legislative body. He was elected to a second five-year term in January 1986. He was replaced in a popular election on 17 February 1991, by President Monteiro.
The prime minister, who heads the government, is nominated by the Assembly, and appointed by the president. The Council of Ministers is appointed by the president on the recommendation of the prime minister. Presently, the unicameral National Assembly or Assembleia Nacional consists of 72 seats with members elected by popular vote to serve five-year terms.
The constitution was amended on 28 September 1990 to legalize opposition parties and revised again in 1992. It underwent a major revision on 23 November 1995, substantially increasing the powers of the president, and a further revision in 1999, to create the position of national ombudsman (Provedor de Justica). It guarantees human rights and includes the principle of the separation of powers, a market-based economy, and individual rights and liberties.