There is a view that when the exclusionary rule was clarified, it should be automatically and mandatorily excluded from evidence if there is an offense by investigative agencies. I think this is due to the trauma of illegal investigations that have historically existed in Korea, but the benefits to criminals from minor misconduct by investigative agencies are too great. In fact, in South Korea, there are cases where evidence is excluded even when there is evidence of harm or guilt, as a deterrent effect to curb misconduct, making it difficult for victims to seek redress.
 The exclusionary rule has certainly contributed to the transparency of investigative practices, as law enforcement agencies are more careful in their investigations. However, quasi-appeals and other administrative or civil sanctions can be sufficient deterrents to illegal investigations. As Japan's theory of relative exclusion shows, it is necessary to use relative and discretionary exclusion rather than mandatory and absolute exclusion in terms of the gravity of the offense and the deterrence of illegal investigations. This is especially true in areas where the standards are not yet clear, such as digital evidence.
 Minor misconduct investigations, especially for digital evidence, are often committed by investigators without recognizing the legality or illegality of the violation. Investigators need to be educated, especially if they have never dealt with cyber crime and only occasionally encounter digital evidence.
 Just as the responsibility of intent and negligence is differentiated in substantive law, it should not be judged only by the result of a criminal investigation without judgment of intent and negligence in procedural law. Guidelines for search and seizure of digital evidence should be established, educated and publicized to law enforcement agencies. Evidence should not be excluded because it is an illegal investigation, without agreement on the appropriate process, in a vague state, and without providing criteria.
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