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As a key role in the defense system and the undertaker of defense functions, lawyers should enjoy extensive litigation rights. However, at all stages of criminal proceedings, lawyers will face various institutional obstacles when performing their defense duties. It is difficult for lawyers to practice because they ignore the defense position of lawyers in the investigation stage. In the stage of examination and prosecution, the defense function of lawyers is restricted, and defense lawyers cannot defend. The defense function will be weakened because the lawyer's defense in the trial process is despised. We should revise relevant laws, improve the professional quality of lawyers, reform and construct the defense system, re-examine procedural justice and realize judicial justice.