One-party states

A one-party state, single-party state, one-party system, or single-party system is a type of state in which one political party has the right to form the government, usually based on the existing constitution. All other parties are either outlawed or allowed to take only a limited and controlled participation in elections. Sometimes the term de facto one-party state is used to describe a dominant-party system that, unlike the one-party state, allows (at least nominally) democratic multiparty elections, but the existing practices or balance of political power effectively prevent the opposition from winning the elections.

One-party states explain themselves through various methods. Most often, proponents of a one-party state argue that the existence of separate parties runs counter to national unity. Others argue that the one party is the vanguard of the people, and therefore its right to rule cannot be legitimately questioned. The Soviet government argued that multiple parties represented the class struggle, which was absent in Soviet society, and so the Soviet Union only had one party: the Communist Party.

Some one-party states only outlaw opposition parties, while allowing allied parties to exist as part of a permanent coalition such as a popular front. However, these parties are largely or completely subservient to the ruling party, and must accept the ruling party's monopoly of power as a condition of their existence. Examples of this are the People's Republic of China under the United Front, or the National Front in former East Germany. Others may allow non-party members to run for legislative seats, as was the case with Taiwan's Tangwai movement in the 1970s and 1980s, as well as the Soviet Union.

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