China's "Public Security Administration Punishment Law" has made relevant provisions on the use of private resort for investigation, and private detectives are likely to be suspected of breaking the law. Moreover, it is also controversial whether the evidence obtained by private investigation can be recognized by the court.
Legal basis: Article 67 of the Civil Procedure Law of People's Republic of China (PRC). The people's court has the right to investigate and collect evidence from the relevant units and individuals, and the relevant units and individuals may not refuse. The people's court shall distinguish the authenticity of the documents submitted by the relevant units and individuals, and examine and determine their validity.
Article 19 of the Criminal Procedure Law of People's Republic of China (PRC) governs the investigation of criminal cases, which shall be conducted by public security organs, except as otherwise provided by law. Crimes such as illegal detention, extorting confessions by torture, and illegal search. The people's procuratorate may file a case for investigation of illegal acts found by judicial personnel in the process of legal supervision of litigation activities. If a major criminal case of a functionary of a state organ under the jurisdiction of a public security organ needs to be directly accepted by a people's procuratorate, it may be placed on file for investigation upon the decision of a people's procuratorate at or above the provincial level.
Article 42 of the Law of People's Republic of China (PRC) on Public Security Administration Punishment, anyone who peeks, takes candid photos, eavesdrops or spreads others' privacy shall be detained for not more than five days or fined not more than 500 yuan; If the circumstances are serious, they shall be detained for not less than five days but not more than ten days, and may also be fined not more than 500 yuan.