Legal analysis: If it is illegal but not suspected of committing a crime, the public security organs have not taken compulsory measures to monitor the residence, but it is completely illegal for the police to monitor it 24 hours a day and install cameras at home. The parties have the right to complain to their superior public security organs or procuratorates and demand that their illegal acts be corrected. If losses are caused to the parties concerned, they shall be liable for compensation.

Legal basis: Provisions on Procedures of Public Security Organs Handling Criminal Cases

Article 106 An application for residential surveillance of a criminal suspect shall be made, stating the reasons for residential surveillance, the ways to adopt residential surveillance and the regulations to be observed, and a decision on residential surveillance shall be made with the approval of the person in charge of the public security organ at or above the county level. The decision on residential surveillance shall be read to the criminal suspect, who shall sign and fingerprint it.

Article 112 The public security organ may use electronic monitoring, irregular inspections and other monitoring methods to monitor the residents under surveillance. In the process of investigation, the public security organ can monitor the telephone, fax, letter, mail, internet and other communications of the criminal suspect under surveillance. Article 113 Where a public security organ decides to monitor residence, it shall be executed by the police station in the place where the residence is monitored or the designated place of residence, and the case-handling department may assist in the execution. When necessary, it can also be executed by the case-handling department, with the assistance of the police station or other departments.