Constitutional law is the study of foundational or basic
laws of nation states and other political organizations.
Constitutions are the framework for
government and may limit or define the authority and procedure of political bodies to execute new laws and regulations.
Not all nation states have codified constitutions, though all such states have a jus commune, or law of the land, that may consist of a variety of imperative and consensual rules. These may include customary law, conventions, statutory law, judge made law or international rules and norms.
Constitutional laws may often be considered second order rulemaking or rules about making rules to exercise power. It governs the relationships between the judiciary, the legislature and the executive with the bodies under its authority. One of the key tasks of constitutions within this context is to indicate hierarchies and relationships of power. For example, in a unitary state, the constitution will vest ultimate authority in one central administration and legislature, and judiciary, though there is often a delegation of power or authority to local or municipal authorities. When a constitution establishes a federal state, it will identify the several levels of government coexisting with exclusive or shared areas of jurisdiction over lawmaking, application and enforcement.
Human rights or civil liberties form a crucial part of a country's constitution and govern the rights of the individual against the state. Most jurisdictions, like the United States and France, have a single codified constitution, with a Bill of Rights. A recent example is the Charter of Fundamental Rights of the European Union which was intended to be included in the Treaty establishing a Constitution for Europe, that failed to be ratified. Perhaps the most important example is the Universal Declaration of Human Rights under the UN Charter. These are intended to ensure basic political, social and economic standards that a nation state, or intergovernmental body is obliged to provide to its citizens.
