legal ground
Article 37 of the Criminal Procedure Law of People's Republic of China (PRC) * * * Defender's duty is to put forward materials and opinions on the innocence, light crime or reduction or exemption of criminal responsibility of criminal suspects and defendants according to facts and laws, and safeguard the litigation rights and other legitimate rights and interests of criminal suspects and defendants. Article 38 A defense lawyer may provide legal aid to a criminal suspect during investigation. Acting as an agent for complaints and accusations; Apply for changing compulsory measures; Ask the investigation organ about the crimes and cases suspected by the criminal suspect, and put forward opinions. 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.