Legal basis: Criminal Procedure Law of People's Republic of China (PRC).
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 39 From the date of examination and prosecution by the People's Procuratorate, defense lawyers may consult, extract and copy the case files. Other defenders may also consult, extract and copy the above materials with the permission of the people's court or the people's procuratorate.