In 2003, some cases were reported to Attorney General of Korea in Supreme Prosecution Service, in which the suspect in detention rejected the request of the prosecutor to attend at his office. Previously, the Prosecution Service interpreted the request to attend for interrogation of the suspect to have the power to impose the duty on the suspect. But in the Academic circles, the majority viewed the request to have no power to impose the duty. Thus they explained the suspect may refuse to attend and during the interrogation leave the office anytime. The suspects who refused to attend rely on the view of the majority of the literature. The Prosecution Service insisted that the interrogation system of Korean Criminal Procedure give the prosecutor and the judicial police the authority to impose the duty to attend on the suspect, especially the duty to attend and to stay on the suspect in arrest or detention. The duty could be forced by arrest warrant or detention warrant. The provision of detention(§ 69, Korean Criminal Procedure) give the definition that it includes the power to take the suspect to a place and to detain in custody. The power to take to a place should be interpreted to include the power to take the suspect to the investigator’s office during the detention. In this Case of the suspect in detention, the Court approved the view of the Prosecution Service and concluded the judicial police officer who took the suspect to the office for interrogation to be lawful. Notwithstanding, the Court explained the character of the interrogation to be voluntary because the statement of the suspect should not be forced. But it could be said contradictory between the possibility of forcing the duty to attend and stay against the suspect’s will and the character of voluntainess. The compulsory nature could be said to be proper to this system.

In this case, the appeal court says, the fact that the defendant used the privilege against self-incrimination and denied answering the questions of the police in the investigative process could not be used as evidence for evaluating the charge to the disadvantage of the defendant. This reference is appropriate. But the principle that we must not use the fact of no answer as evidence for regarding the assertion of the defendant as unreliable should not be confused as a principle that we must give an advantage to the no answer defendant. No answer could not prohibit the fact finder from infering truth from the indirect circumstantial facts. In this case, the defendant insisted that the drug in his body was not injected by him and he did not know how it was in his body. As two persons known visited him the day of arrest and he saw they put injectors in the waterpot, he thouhgt propably they injected the drug in his body in a stealthy way. But the defendant only insisted this story and did not give any clue with which this story could be checked up and for identifying the two persons. Therefore his assertion should be valued as unreliable because of the unreliability of the assertion itself, not because of the fact of no answer. And as the subjective factors as perception, intention, knowing etc could be infered by indirect factors, in this case, the fact that the defendant injected the drug voluntarily could be presumed from the fact that he was arrested in the intoxication in his room, there was none in his room when he was arrested, injectors were founded in his room. So the fact-finding of the court would be said inappropriate.On the other hand, the appeal court says, when the defendant decided to use the privilege against self-incrimination and not to answer, the police should immediately stop questioning. As in this case the police continued questioning, the interrogation is illegal. But this comment is inappropriate because the current criminal process law recognize the right to question to the public attorney and the police independently to the right of the defendant not to answer. Consequently the police can put questions to the defendant though he uses the privilege. But it is up to the decision of the defendant, whether he refuses all questions from the beginning to the end, or reply partly. As for ruling the interrogation, Korean law is different from the American law. Furthemore, in this case, the questions the police put to the silent defendant were for the name or for affirming whether the defendant would use the privilege or not. Because the questions are not for the fact for the defendant's charge, it would be not illegal with the viewpoint of American law.

The right to counsel is regarded as a basic right not only for a suspect under custody but also for a non-arrested suspect as well. It is a constitutional right founded in Section 1 and 4 of Article 12, and Article 27 of Constitution. The right to counsel includes the right entitled to have the presence of counsel during interrogation by law-enforcement. The Criminal Procedure Law revises to guarantee all suspects have rights to counsel during interrogation. The right to counsel is a constitutional right which is materialized at a subordinate criminal procedural law. Therefore, it shall be differentiated from other statutory rights not directly derived from Constitution. According to the Criminal Procedure Law, the right to counsel during interrogation can be exercised by both suspects and counsels. However, such a right entitled to a counsel is not a constitutional right, which shows distinctive difference from a suspect-originated right to counsel.

The Criminal Procedure Act of Korea has not had an explicit provision for the right to the presence of counsel during interrogation until the Article 243-2 of the revised Act took effect on and after January 1, 2008. Whether being in custody or not, a suspect is entitled to have counsel present during interrogation. But while the right to counsel has been the constitutional right, there was discussions on the content and extent of the right. the Article 34 of the previous Act provided the right to counsel for only a suspect in custody and the Article 243 of the previous Act had prescribed only an investigation officer or policeman as those who could be present during interrogation. So the question that a suspect could have a counsel present during interrogation was raised in the practice and the academic circles of law. Many of them had denied the right to the presence of counsel during the interrogation. In November 2003, the Supreme Court of Korea had held that a suspect in custody had the right to the presence of counsel during interrogation. And in September 2004, the Constitutional Court of Korea had determined to confer the right on a suspect without custody. There were advances of the right to counsel through these decisions in Korea. After the 2007 criminal procedure reform, the Act has an explicit provision for the right. Therefore, a suspect is entitled to have a counsel present during the course of investigation and is allowed to get advice from the counsel. Also the counsel is allowed to be present with the client during interrogation. However, unlike the right of a suspect, the right of a counsel is not granted by the Constitution of Korea but by the Criminal Procedure Act of Korea.

On the evidence for the impeachment, in literature, four problems are in discussion. At first, whether a hearsay evidence is admissible for impeachment, although it is not admissible in view of the hearsay rule. Second, whether the oral evidence of the defendant in trial is impeachable, and whehter the defendant's pre-trial statements protocol of the police is admissible for impeaching the oral evidence of the defendant in trial. At last, whether the authentification is required for the admissiblity of the hearsay written statement for impeachment. For first problem, though a hearsay evidence is not admissible according to the hearsay rule, it is admissible for impeachment. The hearsay rule is operated only where pre-trial statement is produced for asserting the truth of the statement. Because impeachment is not asserting the truth of the pre-trial statement, but swaying the crediblity of the oral evidence in trial, hearsay rule is not operated when the evidence is produced for impeachment. For second problem, the oral evidence of the defendant in trial can be impeached for the appropriate way of truth-finding. In practice, the prior inconsistent statement of the defendant can be often used for impeaching the oral evidence of the defendant in trial. § 312 ② of the Korean Criminal Procedure Act provides that the defendant's pre-trial statesments protocol is not admissible when the defendant or the counsel of the defendant denies the truth of the statesment. Because of the provision, some say that the defendant's pre-trial statesments protocol is not admissible for impeachment when the defendant or the counsel of the defendant denies the truth of the statesment. But the Court admits the defendant's pre-trial statesments protocol although the defendant or the counsel of the defendant denies the truth of the statesment, and it is with me on that. For the last problem, the majority in literature and the Court are with the opinion that the authentification is not required for the admissiblity of the hearsay written statement for impeachment. In this point I cannot agree with the Court. The requirement of the authentification is essential for producing all the evidences. It is a different rule from the hearsay rule. In my opinion, It could be said that the majority and the Court confuse the difference. It should be said that a hearsay written statement cannot be used for impeachment when it is not authentifcated.