Japan adopts the principle of prosecution by the state. Under this principle, the right to prosecute is exclusively granted to public prosecutors. Public prosecutors are also granted broad discretion upon prosecution. However, public prosecutors may misjudge a case and make a decision of non-prosecution against the suspect who should be prosecuted. For this reason, legal procedures have been established for the relief of complainants, victims and others against the disposition where the public prosecution is not raised (disposition of non-prosecution) by public prosecutors. These procedures include the right to request reviews by the Committees for the Inquest of Prosecution and the right to file applications for committing a case to a competent district court for trial (also called the quasi-prosecution procedure).
  The system of request for reviews by the Committee for the Inquest of Prosecution was established under the Law for the Inquest of Prosecution (Law No. 147 of 1948). In light of the spirit of the Constitution, this law was promulgated together with the Code of Criminal Procedure in July, 1948 (and enforced on the 12th of the same month), with the aim of reflecting as much public opinion as possible to ensure that the right of public prosecution would be properly exercised. The system of applications for committing a case to a court for trial is designed to allow complainants or accusers of various types of offenses including abuse of authority of public officials, who have an objection to the disposition where the public prosecution is not raised, to request to commit cases to a competent district court for trial. Such competent district court for trial which has accepted such request makes a determination to request cases to be committed to courts for trial, when there exists a reason for the request. Due to such determination, the public prosecution is deemed to have been raised regarding the case. And the court will designate a person who maintains the public prosecution among the lawyers, and cause them to perform the duties of a prosecutor.
  In practice, there is also a non-legal system for relief whereby complainants may appeal against the disposition of non-prosecution by pubic prosecutors. They may request the chief prosecutor of a higher public prosecutors office to exercise the power of supervision. Upon receiving such complaints, the chief prosecutor of the higher public prosecutors office reviews the disposition and notifies the complainant of the result of the review.