Legal basis: Article 35 of the Lawyers Law of People's Republic of China (PRC). According to the needs of the case, the entrusted lawyer may apply to the people's procuratorate or the people's court for collecting and obtaining evidence or to the people's court for notifying witnesses to testify in court. If a lawyer investigates and collects evidence by himself, he may, with the lawyer's practice certificate and the certificate of the law firm, investigate the situation related to undertaking legal affairs with the relevant units or individuals.
Criminal Procedure Law of the People's Republic of China
Article 41 Defenders who believe that the evidence materials collected by public security organs and people's procuratorates to prove the innocence or minor crimes of criminal suspects and defendants have not been submitted have the right to apply to the people's procuratorates and people's courts for retrieval.
Article 43 With the consent of witnesses or other relevant units and individuals, defense lawyers may collect materials related to this case from them, or apply to the people's procuratorate or the people's court to collect and obtain evidence, or apply to the people's court to notify witnesses to testify in court.
With the permission of the people's procuratorate or the people's court, and with the consent of the victim or his close relatives or witnesses provided by the victim, the defense lawyer may collect materials related to the case from them.