Abstract: To strike a balance between crime punishment and human rights protection in the investigation of duty-related crimes, supervisory legislation necessitates and justifies granting the right to legal assistance to the person under investigation. However, during the investigation stage of duty-related crimes, there are still challenges in fully applying this right to legal assistance. The causes of these challenges include the current reforms' emphasis on authority and efficiency, which neglects the value of human rights protection, and considerations related to the complex and unique nature of duty-related crimes, such as preventing third-party interference in investigations. As a third-party provider of legal assistance, duty lawyers possess clear institutional advantages when participating in investigations of duty-related crimes. It is necessary to define the specific conditions under which duty lawyers can intervene in these investigations, to ensure that they provide effective legal assistance, and clarify their obligations to promote the rule of law in reform efforts, thus achieving effective alignment between the supervision law and the criminal procedure law.

Key words: right to legal assistance, duty-related crime investigation, duty lawyer, procedural alignment, rights protection