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.
Single party rule is justified as a means whereby certain elites can retain power accrued through corruption and patronage.
Single party rule provides unity where otherwise tribal and ethnic differences would prevail and undermine the stability of the country.