In a case of public prosecution, it is generally necessary to go through the steps of investigation by public security organs, prosecution by procuratorates, court trial, etc., so as to determine whether the suspect is guilty, and if so, what is the crime and what criminal punishment should be imposed. In judicial practice, a criminal case can be revoked by the public security organ in the investigation stage, a decision not to prosecute can be made in the examination and prosecution stage of the procuratorate, and the suspect can be declared innocent in the court trial stage.