=The Common Law.=—Speaking broadly the system of jurisprudence which American courts administer is made up of three branches, known as common law, statutory law, and equity. Of these the common law is made up of various time-honored usages, some of which go back many hundreds of years. The common law began its growth in mediaeval England when there were very few written rules, and the courts found it necessary to decide cases in accordance with the usages or customs of the people. Gradually these decisions became uniform, one court following the example of another, until this body of usages interpreted by judicial decision became “common” or universal throughout the whole realm of England although it had never been so established by any action of parliament. Thus the rule developed that no man should be compelled to testify against himself, that mere hearsay should not (with certain exceptions) be received as evidence, that all witnesses should be put upon oath, that questions of fact should be decided by juries, that agreements to restrain trade in an unreasonable manner were punishable, and so on.[143] During several centuries a great body of legal rules developed in this way and the system of common law was brought by the English colonists to America, where it speedily took root and was administered by the colonial courts.[144] After the Revolution it was continued and it still remains the groundwork of the law in all the states except Louisiana. Of course it has been gradually modified during the past hundred or more years by court decisions and by statutes, and it still keeps on changing. =Statutory Law.=—Second, there is statutory law. This is law made by definite action of the people or their representatives. Constitutions are in effect statutory law, supreme statutory law. Laws enacted by the people through the initiative and referendum are statutory law. [Sidenote: Statutes.] Most statutory law, however, consists of laws made by Congress, by the state legislatures, by city councils, and by other regular lawmaking bodies.[145] These enactments supplement or alter the common law. Until a statute is passed affecting any question, the common law prevails. Whenever a statute conflicts with a provision of the common law, the statute prevails. But when ordinary statutes conflict with the constitution, the constitution prevails. Enormous numbers of statutes are enacted each year by Congress and the legislatures of the forty-eight states. They now form the larger part of the whole system of law.