How long does public security investigation usually take?

Legal analysis: the time required for court investigation and evidence collection is: the duration of ordinary procedure is six months, and the duration of summary procedure is three months. The application for investigation and evidence collection shall be filed seven days before the expiration of the time limit for providing evidence designated by the court, and the time for investigation and evidence collection shall be counted within the time limit for court hearing.

Legal basis: Criminal Procedure Law of People's Republic of China (PRC).

Article 156 The period of investigation and detention of a criminal suspect after his arrest shall not exceed two months. If the case is complicated and cannot be concluded at the expiration of the time limit, it may be extended for one month with the approval of the people's procuratorate at the next higher level.

Article 157 For particularly serious and complicated cases that are not suitable for trial for a long time due to special reasons, the Supreme People's Procuratorate shall report to the NPC Standing Committee for approval to postpone the trial.

Article 158 If the investigation of the following cases cannot be concluded within the time limit stipulated in Article 156 of this Law, it may be extended for two months with the approval or decision of the people's procuratorate of a province, autonomous region or municipality directly under the Central Government: (1) major and complicated cases in remote areas with very inconvenient transportation; (2) Major criminal group cases; (3) Major and complicated cases of escaping crime; (four) major and complex cases involving a wide range and difficult to obtain evidence.