Legal provisions:
Article 41 of the Criminal Procedure Law states that a defense attorney, with the consent of the witnesses or other relevant units and individuals, may collect from them materials related to the case, or may apply to the people's procuratorate or the people's court for the collection and retrieval of evidence, or apply to the people's court for notification of the witnesses to appear in court to testify.
Defense lawyers, 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 the witnesses provided by the victim, may collect from them materials related to the case.