In principle, criminal case trials of the first instance are adjudicated by district, family, and summary courts. Koso appeals against judgements by these courts of first instance are taken to the high courts, and trials of the last instance against the results of these koso appeals are adjudicated by the Supreme Court.
District Courts, despite not having jurisdiction for offenses only subject to punishment by fines or something less, offenses coming under the exclusive jurisdiction of the family courts, or offenses for which the high courts have jurisdiction of the first instance, have jurisdiction of the first instance for prosecution of offenses.
Family Courts have jurisdiction of the first instance for prosecution of adult criminal cases which harm the welfare of juveniles, as well as examination of juveniles as stipulated in the Juvenile Law.
Summary Courts have jurisdiction of the first instance for prosecution of offenses only subject to punishment by fines or something less, offenses for which fines are stipulated as an optional punishment, offenses of habitual gambling, opening a place of gambling, etc. , for the purpose of profit, larceny, attempted larceny, embezzlement (Article 252 of the Penal Code), receiving stolen goods, and other offenses other than those coming under the exclusive jurisdiction of the family courts.
High Courts have jurisdiction of the first instance for koso appeals against judgements by district, family, and summary courts, kokoku appeals against decisions and orders of these courts(excluding kokoku appeals coming under the authority of the Supreme Court), and prosecution of insurrection and other offenses for which the high courts have jurisdiction of the first instance.
  The Supreme Court has jurisdiction of the jokoku appeal and for kokoku appeals as expressly stipulated by law.
  Trials of the first instance in district and family courts are conducted under the ordinary proceedings for public trial. Trials of the first instance in summary courts are conducted under the ordinary proceedings for public trial or under summary proceedings(hereinafter, trials conducted under the ordinary proceedings in courts of the first instance are referred to as"ordinary first instance").