Rule of law

Laws, not the will of individual rulers, govern. Law must be public, general, prospective and applied equally, and officials must be accountable under it.

A. V. Dicey (1885) stressed supremacy of regular law and equality before it. Lon Fuller listed eight desiderata of legality, such as clarity, non-retroactivity and congruence between rules and official action. Joseph Raz defended a formal, "thin" conception; Tom Bingham and others argued for "thicker" versions that include fundamental rights. Brian Tamanaha mapped these contrasts.

• Clause 39 of Magna Carta (1215) barred punishment except by lawful judgment or the law of the land.
• The United Nations describes the rule of law as accountability to laws that are publicly promulgated, equally enforced and independently adjudicated.
• The World Justice Project defines it through accountability, just law, open government and accessible and impartial justice, and publishes an annual index.

Thin accounts can be satisfied by unjust but orderly law ("rule by law"), thick accounts may merge the rule of law with all good government, and promoting it abroad has had mixed results.

The ideal is widely endorsed, yet there is no agreed definition or single measure, and evidence on what causes it is contested.