Political rule by one party involves the refusal of the right to opposition; the banning both of existing parties and of the formation of others; imprisonment of leaders and followers of other parties; and general repression. The situation manifests as political instability and may cause social and political conflict or general apathy.
In 1990, out of 45 black African nations, only 4 (Botswana, the Gambia, Mauritius and Senegal) allow their people to vote, choose their leaders and express themselves freely. In sub-Saharan Africa, only 5 can be considered multi-party democracies. Military dictatorships prevail in 23 countries, where no political parties are permitted, and the remainder are one-party states ruled by dictators-for-life.