One may recognize three chief factors in the administration of criminal justice, namely, men, machinery, and environment. Justice is administered by men. These men administer it by means of legal and political institutions. Also they do so in a certain social and political and economic environment. From a historical standpoint there are five elements in American criminal law. The first is the inherited (or received) seventeenth-century English criminal law and procedure. The second element is independent development of criminal law in colonial America. The third element is Blackstone's Commentaries on the Laws of England. The fourth element is American building in the nineteenth century upon post-Revolutionary English decisions. Finally, there is American legislation of the legislative reform movement, which begins soon after the Revolution and continues until the Civil War. Most important among the primitive legal materials which still have a place in our criminal law is the Germanic idea of the truce or peace.