In practice, constitutions can: achieve near-unalterable status, as in the United States; be frequently rewritten, as in many other countries in the Western hemisphere; be used to justify authoritarian forms of rule; or come to be entirely disregarded.

Israel, Britain and New Zealand are outliers, as they do not have constitutions, said Hanna Lerner, the author of “Making Constitutions in Deeply Divided Societies.” The United Kingdom and New Zealand rely on common law, bodies of legal thinking and precedent developed over centuries, which serve a de facto constitutional role.