The prosecutor's appeal is dismissed.

1. The court below erred by misapprehending the legal principles on the grounds that the defendant's act of not guilty on the ground that the defendant's act did not meet the legitimacy of the purpose, the means or method of the use, the reasonableness of the protected legal interest and the balance between the protected legal interest and the infringement legal interest, and supplementary nature, etc., and thereby constitutes a justifiable act even though he did not meet the legitimacy of the purpose, the means or method of the use, the reasonableness of the protected legal interest and the violation legal interest.

2. Determination

A. In full view of the evidence duly adopted and examined, the lower court determined that the Defendant’s act constitutes a justifiable act and thus, constitutes a justifiable act, since it is reasonable to the extent permissible by social norms in light of its nature, purpose, means, and intent, etc., since the Defendant, a train crew member, discovered D, demanded him to produce boarding tickets, but D refused to do so, took a bath and knife the Defendant’s face, and attacked the Defendant, such as spiting spits, and spiting DNA on the Defendant’s face, and exercising force, such as cutting off DNA for the convenience of other passengers.

B. Examining the reasoning of the judgment below in light of the records, the above fact-finding and judgment of the court below are just, and there is no error of misapprehending the legal principles as alleged by the prosecutor.

3. In conclusion, the prosecutor's appeal is dismissed in accordance with Article 364 (4) of the Criminal Procedure Act on the ground that it is without merit. It is so decided as per Disposition.