In everyday forms of legal consciousness or popularised interpretations of law in the field of law enforcement there is often a tendency to identify the categories of «legality» and «enforceability». This practice can be produced both by extra-scientific forms of determination, consisting in the effort to form in the legal culture of the population the image of the unity of law and right and trivial substitution of concepts that creates a serious methodological problem of scientific understanding of the phenomenon of law itself. The authors therefore set the objective of this research - to analyse the mentioned categories. The article outlines the author’s position in understanding the correlation between the categories of «legality» and «enforceability», which is fundamentally important for the methodology of legal science, and theoretically analyses the practical forms of representation of this correlation on the example of firearms use by police officers. The theoretical basis of the research are the studies of national and foreign academics. Methodology. In the process of working with the material the systematic method, as well as methods of comparative legal, historical and legal analysis and formal logic were used. Results. The authors find out that the definition of the correlation between the concepts of «legality» and «enforceability» is reasonable to conduct on the methodological basis of differentiation of the concepts of «right» and «law», which makes it possible to consider enforceability as a broader concept that includes elements of situational discretion. The justification for this conclusion is that the concept «enforceability» means the compliance of certain social phenomena to law, which can be understood not only as the norms of law, but also the system of natural rights of social subjects, determined by socio-cultural and moral norms of social life.