In 1225, during the regency of Hōjō Yasutoki, the Kamakura shogunate set up the hyōjōshū, a council. With the regent and his co-signer present, the council deliberated important matters of law and government and decided lawsuits.
In 1232, the shogunate issued the Goseibai Shikimoku, a code of law for the warrior class.