The article reviews some issues of ensuring legality of judgments adopted by justices of the peace in criminal cases. Features characteristic of the activities of justices of the peace and risks that may affect the quality and legality of their judgments, are highlighted. Based on a study of the practice of higher courts, common violations committed by justices of the peace are identified, some examples are provided. Special attention is paid to the issue of assessment of insignificance of an act. Some proposals aimed at ensuring legality of judicial proceedings are brought forward