The participation of legal counsel and the provision of effective defense are crucial for ensuring procedural fairness and protecting human rights in criminal justice systems. With the introduction of the leniency system for pleading guilty and accepting punishment, China’s criminal procedure has increasingly emphasized efficient case resolution, making the comprehensive and effective involvement of defense lawyers indispensable. The duty lawyer system serves as a core component of the leniency framework, playing a key role in safeguarding the voluntariness of the accused’s plea and the legitimacy of case outcomes. However, the duty lawyer system in China still faces several structural shortcomings. Although legally defined as legal aid providers and rights protectors, duty lawyers often function merely as witnesses to procedural formalities rather than active defenders. They lack essential litigation rights, which limits their ability to provide informed legal advice. Moreover, there is a persistent ambiguity between their role as rights safeguards and their practical function as collaborators with judicial authorities, compounded by the government shifting legal aid responsibilities onto duty lawyers. To enhance the system’s effectiveness, comprehensive reforms are necessary. These should include clearly defining duty lawyers as defense counsel, expanding their litigation rights, clarifying the primary responsibility for legal aid, broadening the scope of legal aid in criminal defense, and establishing clear standards for evaluating effective legal assistance.