Article 17 1 of the Criminal Procedure Law stipulates: "When a people's procuratorate examines a case and needs supplementary investigation, it may return it to the public security organ for supplementary investigation or conduct investigation on its own. In the case of supplementary investigation, the supplementary investigation shall be completed within 1 month. Supplementary investigation is limited to 2 times. After the supplementary investigation is transferred to the people's procuratorate, the people's procuratorate recalculates the time limit for examination and prosecution. For the case of supplementary investigation, if the people's procuratorate still believes that the evidence is insufficient and does not meet the conditions for prosecution, it may make a decision not to prosecute. "
1. There are two kinds of supplementary investigations. That is, if the public security organ terminates the investigation and the people's procuratorate needs supplementary investigation after examination, it may decide to return the case to the public security organ for supplementary investigation, or it may decide to conduct investigation on its own, and ask the public security organ for assistance when necessary. However, if the people's procuratorate needs to make supplementary investigation on a case that has been investigated by itself, it cannot be returned to the public security organ for supplementary investigation.
2. According to Article 140 of the Criminal Procedure Law and Articles 268 and 269 of the the Supreme People's Procuratorate Rules, a case returned to the public security organ for supplementary investigation shall be completed within one month; The time limit for the people's procuratorate to examine and prosecute shall be recalculated from the date when the supplementary investigation of the case is completed and the case is transferred for prosecution. If the people's procuratorate decides to conduct its own investigation during the period of examination and prosecution, it shall complete the investigation within the period of examination and prosecution.
3. The number of supplementary investigations shall not exceed 2 times. This not only refers to the cases returned to the public security organs for supplementary investigation, but also includes the cases that the people's procuratorate decided to return to the investigation department for supplementary investigation.
4. After supplementary investigation, if the people's procuratorate still thinks that the evidence is insufficient and does not meet the conditions for prosecution, it shall make a decision not to prosecute. The purpose is to safeguard the legitimate rights and interests of criminal suspects, prevent cases from being dragged on for a long time and improve the efficiency of litigation.