Since independence, Ghana has experienced four military coups and ten changes of government. The military ruled Ghana by decree from 1972 to 1979, when an elected constituent assembly adopted a new constitution establishing a unicameral parliament and an executive branch headed by a president. On 31 December 1981, a military coup installed the Provisional National Defense Council (PNDC) as the supreme power; the constitution was suspended and the national assembly dissolved.
A consultative assembly, convened late in 1991 to draw up a new constitution, completed its work in March 1992. The government inserted a controversial amendment indemnifying officials of the PNDC from future prosecution for all acts of commission and omission during their term in office. In an April 1992 referendum, the constitution was approved by 92.5% of voters in a low turnout (58% of those eligible). It provides for a presidential system and a legislature (national assembly) of 200 members. Since the 1992 referendum, the government introduced multiparty competition, with the 1996 and 2000–2001 elections receiving high marks for fairness from international observers.
Rawlings was both chief of state and head of government until his second term expired in December 2000. The president is elected for a four-year term, and the constitution bars a third term. John Agyekum Kufour was elected president in 2000 over Rawlings' vice president and hand-picked would-be successor, John Atta Mills.