In principle, the first instance trials of criminal cases are conducted by district, summary, or family courts. High courts have jurisdiction over Koso appeals against judgments in the first instance, and the Supreme Court has jurisdiction over Jokoku appeals (final appeals) against judgments in Koso appeals.
  District courts are principal courts for the first instance trials, except for (1) offenses subject to punishment by fines, petty fines or misdemeanor imprisonment without work and (2) offenses coming under the exclusive jurisdiction of family courts or offenses for which high courts have the first instance jurisdiction.
  Summary courts have the first instance jurisdiction over (1) offenses subject to punishment by fines, petty fines or misdemeanor imprisonment without work, (2) offenses for which fines are stipulated as an optional punishment, and (3) certain offenses such as habitual gambling. Exceptions are offenses coming under the exclusive jurisdiction of family courts. Summary courts in principle cannot sentence imprisonment or death, but may sentence imprisonment with work of three years or less for certain offenses such as theft.
  Family courts deal with juvenile cases and have the first instance jurisdiction over prosecutions of adult criminal cases against the welfare of juveniles under the Juvenile Act (Act No. 168 of 1948) (certain offenses prescribed by the Child Welfare Ac, etc.).
  High courts have jurisdiction over (1) Koso appeals against judgments by district, family and summary courts, (2) Kokoku appeals against decisions and orders by these courts (excluding Kokoku appeals under the jurisdiction of the Supreme Court), and (3) the first instance of insurrection.
  The Supreme Court has jurisdiction over Jokoku appeals and over Kokoku appeals as specifically stipulated by acts.