The Rule of Law Is the Idea that We Should Be Governed By Known Laws, Not the Arbitrary Decisions of Government Officials; John Adams Called It a Government of Laws, and Not of Men

Another principle that restrains power and creates greater security for the public is the rule of law. This is the idea that we should be governed by known laws, not the arbitrary decisions of government officials – what the American statesman John Adams (1785–1836) called ‘a government of laws, and not of men’.

Classical liberals insist that the law should apply equally to everyone, regardless of gender, race, religion, language, family or any other irrelevant characteristics. It should apply to government officers just as much as to ordinary people; nobody should be ‘above the law’.

To maintain the rule of law requires a system of justice, with independent courts that cannot be manipulated by individuals or governments. There need to be basic judicial principles such as habeas corpus, trial by jury and due process to prevent those in power using the law in their own interests.

The rule of law has another happy consequence – it makes life far more predictable, because it enables us to anticipate how people (including officials) will – and will not – behave. So we can make long-term plans without fear of having them shattered by the caprice of others.

--Eamonn Butler, Classical Liberalism: A Primer (London: Institute of Economic Affairs, 2015), 8-9.