Brazilian law derives from Portuguese, French, Italian and German Civil law and is based on statutes and, partly and more recently, súmula vinculante (stare decisis). The Federal Constitution, in force since October 21st, 1988, is the supreme law of the country and is characterized by its rigid written form. The Constitution organizes the country as a Federative Republic, formed by the indissoluble union of the states and municipalities and of the Federal District. The 26 federate states have powers to adopt their own Constitutions and laws. Their autonomy, however, is limited by the principles established in the Federal Constitution.