The maximum period of criminal detention is 37 days. If there is no evidence to arrest, you must be released. If a person is arrested within the time limit, they will continue to be detained and the investigation of the case will continue.
According to Article 91 of the "Criminal Procedure Law of the People's Republic of China", if the public security organ considers that a detained person needs to be arrested, it shall submit it to the People's Procuratorate for review and approval within three days after detention. . In special circumstances, the time for submission for review and approval may be extended by 1 to 4 days.
For major suspects who commit crimes on the run, commit crimes multiple times, or commit crimes in groups, the time limit for application for review and approval can be extended to 30 days.
The People’s Procuratorate shall make a decision on approving or disapproving the arrest within seven days from the date of receipt of the request from the public security organ to approve the arrest. If the People's Procuratorate does not approve the arrest, the public security organ shall release the person immediately upon receiving the notice and promptly notify the People's Procuratorate of the execution status. If it is necessary to continue the investigation and meet the conditions for release on bail pending trial or residential surveillance, the person shall be released on bail pending trial or placed under residential surveillance in accordance with the law.
Extended information:
Article 85 of the "Criminal Procedure Law of the People's Republic of China" When the public security organ detains a person, it must produce a detention warrant.
After being detained, the offender shall be immediately sent to a detention center for detention, which shall not exceed 24 hours at the latest. Unless notification is impossible or the notification of suspected crimes endangering national security or terrorist activities may hinder the investigation, the detainee's family members shall be notified within 24 hours after detention. As soon as the circumstances preventing the investigation disappear, the detainee's family should be notified immediately.
Article 86 The public security organs shall interrogate the detainee within 24 hours after detention. If it is found that the person should not be detained, he shall be released immediately and a release certificate shall be issued.
Article 87 When the public security organ requests the arrest of a criminal suspect, it shall write a request for approval of the arrest and transfer it together with the case file materials and evidence to the People's Procuratorate at the same level for review and approval. When necessary, the People's Procuratorate may send personnel to participate in the discussion of major cases by the public security organs.
Reference materials:
Baidu Encyclopedia - Criminal Detention
China National People's Congress - Criminal Procedure Law of the People's Republic of China