The discovery of substantive truth is the purpose and raison d'être of criminal procedure law. However, the end does not necessarily justify all means. Criminal proceedings must be conducted by appropriate and fair means. This requires cooperation between the court, the investigating agency, the suspect and the accused, the defense, and the various parties involved in the criminal proceedings. However, obstruction of justice and perverting the law can make the criminal justice process unfair. Among the types of obstruction of justice, the main issue has been whether to punish false statements by witnesses. There are opposing views on whether a general provision should be introduced to punish obstruction of justice. On the other hand, views are divided on whether it can be introduced on a limited basis. However, it is necessary to punish systematic obstruction of criminal proceedings by making false statements to witnesses, especially in political crimes, corporate crimes, and organized crime. It is also possible for officials who are conducting criminal proceedings to distort the law and undermine fair criminal proceedings. Therefore, there are arguments in academia and the National Assembly to introduce a separate crime of perjury. There is a general consensus among academics that the law should be changed. However, there is a division of opinion on the specific method. Perjury can be used by those in power as a tool to violate the independence of the judiciary. Therefore, it is necessary to ensure that those in power, such as high-ranking officials, cannot unduly influence the criminal justice process and distort the law. In addition, prosecutors and judges should not be allowed to distort the law by colluding with those in power. Therefore, even if a crime of distortion of the law is introduced, it is proposed that the penalties should be limited to those who distort the law through the intervention of political power and those who distort the law for political or private interests. It is not advisable for the discussion of obstruction and distortion of the criminal justice process to be rushed into legislation in the midst of political debate. It should be fully debated in the academic realm.