Recently many important parts of criminal procedure was amended by the National Assembly. Especially, the evidence law on the pre-trial statements before the investigative institution and the protocol is greatly changed. Since 2003, some radical administrative judges of the Judicial Administration Center of the Supreme Court, lawyers and professors have insisted that the pre-trial statements before the investigative institution should not be admissible when the declarant change the statement on trial. Only the statement on trial be admissible. They argued this requirement as so-called "trial priority principle". The tendency for the denial of the admissiblity of the protocol of the pre-trial investigation have been developed by the case law of the Supreme Court for the interpretation of the provision for the authentication of the protocol. Criminal procedure requires the authentication for the admissibility of the investigative protocol and provides that the authentication be proved only by the statement of the declarant. The idea of the authentication has been introduced by the drafters for making the investigative protocol one of the exhibits with which the statement in reality can be proved. And the provisions of declarant statement method for the proof of the authentication are to guarantee the presence of declarant in order for the Defendant to raise the objection and cross-examine the declarant as witness. But the Court develops the concept of the substantial authentication. The substantial authentication are the correspondence of the written statements of the protocol with the statements in reality. Another serious interpretation is that the statements of the declarant, with which the authentication can be proved, mean the declarant's approval of the authentication. Moreover, the Court prohibits any other proof for the exisitence of the statements in reality, when the admissibility of the protocol is denied. This interpretation of the Court for the provision of the investigative protocol is far from the original intention of the drafters of korean criminal procedure and especially far from the general theory of evidence law. The radicalists, who lead the discussion in the Presidential Committee on the Judicial Reform(PCJR), go too extreme with the unreasonable tendency of the Court and drafted a bill for the revision of the evidence law which restrict seriously the admissibility of the pre-trial statement before investigative institution, including the public attorney. It is obvious that this tendency be far from trial-priority principle in real meaning. The National Assembly recognized the unreasonableness of the Court's interpretation and the problem of the bill of the PCJR and corrected the bill. According to the corrected bill, the authentication can be proved by the declarant's statements, video-recorded tape or other methods objectively. By this amendment, the unreasonableness of the result which the Court's substantial authentication concept bring about could be partly solved in the future. But the substantial authentication concept survives in the revised code. Therefore it is strange that the protocol can be admissible after the written statements be proved to be correspond with the real statement. Only the method of proof for this correspondence are pluralized. In the future the evidence law should be revised again with the view to the general theory of the evidence law, and then the substantial authentication concept should be excluded.