공범증인면책제도 도입방안에 대한 연구

This study examines the constitutional and procedural validity of introducing a "the Immunity of Accomplice Witnesses" to overcome the limitations of investigating clandestine and sophisticated crimes such as voice phishing, organized crime, and corruption. The primary legal hurdles in establishing a general leniency system involve the potential infringement of the constitutional privilege against self-incrimination and the difficulty of ensuring the voluntariness and reliability of co-conspirator testimony. To address these issues, this research provides an in-depth analysis of the legal evolutions in the United States and the United Kingdom. By examining the "Coextensive Principle" established through U.S. federal statutes and Supreme Court precedents, such as Brown v. Walker and Kastigar v. United States, this study confirms that the essence of the privilege against self-incrimination lies in the "elimination of the risk of criminal prosecution" rather than an absolute right to silence. Based on this finding, it concludes that the codification of "Use and Derivative Use Immunity"—which bars the use of not only direct testimony but also all evidence derived therefrom—is a prerequisite for any Korean legislative model. Furthermore, focusing on the procedural justice emphasized in British case law, such as R v Pipe and R v Hutchinson, this study proposes specific measures to guarantee the voluntariness of statements. It suggests a model that respects the "voluntary choice" of the accused rather than compelling testimony through state power. Finally, as multi-layered safeguards to minimize the possibility of judicial errors inherent in human testimony, this research proposes legislative alternatives: the strict application of the Corroboration Rule to co-conspirator statements and the mandatory "Cautionary Instruction" by the court to the jury or finders of fact.