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.