Legal basis: Criminal Procedure Law of People's Republic of China (PRC).
Article 112 A people's court, a people's procuratorate or a public security organ shall, within the scope of their jurisdiction, promptly examine the materials of reporting, accusing, reporting and surrendering themselves, and if they think that there are criminal facts that need to be investigated for criminal responsibility, they shall file a case; If it is considered that there are no criminal facts, or the criminal facts are obviously minor, and it is not necessary to pursue criminal responsibility, the case shall not be filed, and the complainant shall be informed of the reasons for not filing the case. If the complainant refuses to accept it, he may apply for reconsideration.
Article 115 A public security organ shall investigate a criminal case that has been put on file, and collect and obtain evidence of the criminal suspect's guilt or innocence, whether the crime is minor or serious. An active criminal or a major suspect may be detained in advance according to law, and a criminal suspect who meets the conditions for arrest shall be arrested according to law.