The freedom to form, declare membership in, or campaign for candidates from a political party is considered a measurement of a state's adherence to liberal democracy as a political value. Regulation of parties may run from a crackdown on or repression of all opposition parties, a norm for authoritarian governments, to the repression of certain parties which hold or promote ideals which run counter to the general ideology of the state's incumbents (or possess membership by-laws which are legally unenforceable).

What is considered a measurement of a state's support to liberal democracy?