A. Since the execution of official duties by police officers by mistake of facts or misapprehension of legal principles was not legitimate, the defendant's act does not constitute obstruction of performance of official duties.

B. The lower court’s sentence of unreasonable sentencing (three million won of fine) is too unreasonable.

2. Determination

A. 1) Determination of the assertion of mistake of facts or misapprehension of legal principles is based on the premise of a legitimate performance of official duties by public officials. Whether a certain performance of official duties by public officials belonging to abstract authority is legitimate should be determined objectively and reasonably based on the specific circumstances at the time of the act, and it should not be determined ex post facto in pure objective criteria.

(B) In light of the spirit of substantial direct examination adopted by the Criminal Procedure Act, the first instance court’s determination on the credibility of a statement made by a witness of the first instance court is clearly erroneous, or in exceptional cases where it is deemed significantly unreasonable to maintain the first instance court’s determination on the credibility of a statement made by a witness of the first instance court by the time of closing argument in the appellate trial, in full view of the result of the first instance examination and the result of additional examination of evidence conducted by the time of closing argument in the appellate trial, the appellate court shall respect the determination on the credibility of the statement made by the witness of the first instance (see, e.g., Supreme Court Decisions 91Do453, May 10, 1991; 201Do494, Aug. 23, 2013). According to the evidence duly adopted by the lower court, the Defendant asserted that his father of the first instance court and the police officer were present at the scene at the time of the instant crime, and the mother who was present at the scene at the time of the first instance.