In accordance with the provision of Article 308–2 of Criminal Procedure Act, any evidence obtained in violation of the due process shall not be admissible. This Article newly inserted by Act No. 8496, Jun. 1. in 2007. Since then, there has been a series of a decision on the evidence, including the exclusionary rule, the fruits of poisonous tree doctrine, and the circumstance that would give exceptionally the admissibility of secondary evidence. In addition, there were a number of decisions that required to be prepared in compliance with the due process and proper methods in giving the admissibility of evidence in relation to the protocol, etc. prepared by prosecutor or senior judicial police officer. As a whole, due to the influence of making a stipulation of the exclusion of evidence illegally obtained, it is clear that the case law in the field of evidence law is proceeding in a direction to emphasize the guarantee of the due process. And in accordance with the provision of Article 314(Exception to Admissibility of Evidence) or 316(Statement of Hearsay) (2), in the case of Article 312 or 313, if a person who is required to make a statement at a preparatory hearing or a trial is unable to make such statement, which is impossible to exercise the right of cross–examination, the relevant protocol and other documents shall be admissible as evidence: Provided, that this shall apply only when it is proved that the statement or preparation was made in a particularly reliable state. In relation to the above provisions, court’s decision maintains a more rigorous interpretation as a requirement for admissibility of hearsay evidence. In addition, court’s decision seems to be proceeding to apply strictly requirements for admissibility of evidence of documents or output from the digital storage media, explaining the requirements of seizure and search of digital storage media in response to overall scientific and information– oriented society. And the recent decision describes the problem of establishing the judgment criteria of scientific evidence as a solution to the problem of misuse of science among the problems in the process of interaction between science and law in accordance with the criminal case. In conclusion, it is still a question of how to realize concretely the general principle that the two sets of demands, namely the discovery of substantive truths and the protection of the human rights of defendants (the guarantee of due process and the deterrence of illegal investigation) under the exclusionary rule.

The exclusionary rule is a judge-made doctrine that prohibits introduction of evidence obtained in violation of a defendant's Fourth, Fifth, and Sixth Amendment to the US Constitution. The Fourth Amendment to the US Constitution provides: The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized. The exclusionary rule enforces this constitutional provision by excluding from the trial of a case any evidence that has been obtained by the government through means which violate the Fourth Amendment. The exclusionary rule operates as a bar to the use of evidence obtained as a result of an illegal search or seizure. The US courts have been reluctant to impose exclusion as a judicial remedy for a violation of a federal statute or regulation, or a Federal Rules of Criminal Procedure. The other major civilized country, such as UK, Canada, Japan, France, Italy, and Germany, also have their own exclusionary rule related with the improperly, illegally or unconstitutionally obtained evidence. The revised Code of Korean Criminal Procedure introduced the exclusionary rule of the US to the criminal justice system where Korean Supreme Court has been refusing to apply the rule to the material evidence which is obtained by the illegal search or seizure of the government. It provides that the evidence which is obtained by violating due process of law shall not be admitted. The admission of the evidence, in Korea, depends on whether the government followed the due process of law while the evidence that has been secured by violation of the constitutional right shall be excluded in US. In addition, the major opinion of Korean Supreme Court recently held that, in principle, the exclusionary rule should be applied to the material evidence if the evidence was obtained by the search or seizure process which did not follow the Korean Constitutional Law and Criminal Procedure Law. According to this ruling, there is a chance that the slight violation of the Criminal Procedure Code by investigative agents would result in exclusion. I disagree with this opinion of Korean Supreme Court because this opinion did not deeply considered the one of the goals in criminal procedure - the discovery of the truth. The standard of the exclusionary rule must be whether the illegality of government's violation is substantial or serious considering the spirit of due process of law. It was the minor opinion of that Supreme Court's ruling.