Article 39 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.
Therefore, according to the law, defense lawyers may, with the consent of witnesses or other relevant units and individuals, collect materials related to the case from the people's procuratorate since the date when the people's procuratorate examines and prosecutes the case, 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.
So there is no right to investigate and collect evidence at the investigation stage.
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