Constitutional law

Constitutional law governs the fundamental principles by which a state exercises authority, granting specific powers—such as taxation and spending for public welfare—while also placing limits on government action, like prohibiting arbitrary arrest. This body of law can be understood as second-order rule making: rules about how to make and exercise power. It establishes hierarchies and relationships among the judiciary, legislature, and executive.

In a unitary state, ultimate authority rests with a central administration, though power may be delegated locally. In a federal state, such as India or the United States, the constitution identifies multiple levels of government with exclusive or shared jurisdictions over lawmaking and enforcement. Some federal systems, notably the U.S., maintain separate federal and state judiciaries with their own supreme courts; India, by contrast, has a single judiciary divided into district courts, high courts, and a national Supreme Court.

Human rights

Human rights or civil liberties form a crucial part of most constitutions, upholding individual rights against the state. Many jurisdictions, including the United States and France, have a codified constitution with a bill of rights. Canada’s uncodified constitution nonetheless includes the Canadian Charter of Rights and Freedoms. The United Kingdom lacks an entrenched document, relying instead on statute, case law, convention, and international agreements like the European Convention on Human Rights.

In the landmark case Entick v Carrington, judges derived constitutional principles from common law, ruling that a government minister’s warrant did not justify a search without statutory or court authority. Common law nations emphasize judicial precedent as a source of law, while civil law jurisdictions give legislators more power to modify law and place less emphasis on case law. Consequently, common law judiciaries are often adversarial and independent from both legislature and prosecution, whereas civil law systems tend toward an inquisitorial approach. International enactments, such as the Universal Declaration of Human Rights and the European Union’s Charter of Fundamental Rights, also aim to ensure basic political, social, and economic standards.