Constitutional law refers to rights carved out in the federal and state constitutions. The majority of this body of law has developed from state and federal supreme court rulings, which interpret their respective constitutions and ensure that the laws passed by the legislature do not violate constitutional limits.
Constitutional laws may often be considered second order rule making 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. Some federal states, most notably the United States, have separate and parallel federal and state judiciaries, with each having its own hierarchy of courts with a supreme court for each state. India, on the other hand, has one judiciary divided into district courts, high courts, and the Supreme Court of India.
Another main function of constitutions may be to describe the procedure by which parliaments may legislate. For instance, special majorities may be required to alter the constitution. In bicameral legislatures, there may be a process laid out for second or third readings of bills before a new law can enter into force. Alternatively, there may further be requirements for maximum terms that a government can keep power before holding an election.