Even if the defendant did not have understood and consented to the meaning of voluntary accompanying, the procedure of voluntary accompanying is illegal, and the request for measurement of drinking alcohol in this case made after illegal voluntary accompanying is also implemented in an illegal arrest state. Thus, the failure to comply with the request for measurement of drinking alcohol does not constitute the rejection of measurement of drinking alcohol.

Defendant was driving alcohol at the time;

There was no reasonable ground to suspect, and there was no perception that drinking is subject to criminal punishment when refusing or refusing to measure drinking by drinking.

Supreme Court Decision 2009Do6717 Decided June 30, 201 regarding the grounds for appeal clearly states the principle of voluntary investigation. Article 199(1) of the Criminal Procedure Act stipulates that an investigator accompanying a suspect to an investigative agency, etc. in the form of obtaining consent from the investigative agency in the course of an investigation does not have any means to suppress the suspect's physical freedom, and even though it is substantially similar to the arrest, it cannot be systematically and practically guaranteed as well as systematically. Furthermore, it is highly likely that the Constitution and the Criminal Procedure Act are contrary to the principle of the Criminal Procedure Act, such as the provision of various rights guarantee devices granted to the suspect under arrest and detention on the ground of the transfer of regular arrest and detention. Thus, the investigator's accompanying of the suspect was carried out only by his voluntary will, such as where it is acknowledged that the suspect, prior to the accompanying, could refuse the accompanying of the suspect at any time, may leave the investigative agency freely or by accompanying the suspect.