First, lawyers usually meet criminal suspects and defendants in custody in places of detention, and the interviews are not monitored or recorded. In order to ensure the safety of guards and meetings, the detention center can install video surveillance equipment at the venue. 2. Article 38 of the Criminal Procedure Law: Defence lawyers may provide legal aid to criminal suspects 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 A defense lawyer may meet and correspond with a criminal suspect or defendant in custody. Other defenders, with the permission of the people's courts and people's procuratorates, may also meet and correspond with criminal suspects and defendants in custody.